Watch Strap Size Guide: Lug Width by Brand

Choosing a watch strap always starts with one measurement: the lug width. This distance between the two lugs of the case, expressed in millimetres, determines the width to order — and nothing else does. A one-millimetre error makes fitting impossible.

This guide explains how to take that measurement accurately, which length and buckle to choose, how the attachment systems work, and which materials suit which use. It ends with the lug width of 245 watch models.

Since 2010, we have been advising collectors and enthusiasts on the choice of their straps. A question about your watch? Our team is available on +33 9 80 84 88 08.

choosing a watch strap on laboiteamontres.com

Measuring a watch strap: lug width, buckle, length
Attachment systems: spring bars and Quick Release
Changing a strap: removal and fitting
Materials: leather, rubber, nylon
Matching colours
Pin buckle or deployant clasp?
Lug width by brand: 245 models
FAQ — Size and dimensions
Our collections

Measuring a watch strap: lug width, buckle, length

Measuring the lug width

The key measurement of a strap is its width at the attachment point. It is taken on the watch case itself, between the two lugs that hold the strap. This distance is called the lug width.

Measure the exact gap with a vernier caliper, or failing that with a ruler. Standard widths are 16, 18, 20, 22 and 24 mm. Sizes of 19 and 21 mm exist but remain uncommon.

An example: if your watch measures 20 mm between the lugs — the case with almost every Rolex — choose a strap from the 20 mm category.

One piece of advice avoids most mistakes: do not measure your old strap, measure the gap on the watch. A strap deformed by wear, or wrongly sized in the first place, would lead you to order the wrong width.

measuring the lug width of a watch strap

The buckle width

The buckle is measured the same way, on its inner section, where the strap is held by a spring bar. It is almost always narrower than the strap, by 2 mm.

A 20 mm strap therefore takes an 18 mm buckle: this is referred to as 20/18. A 24 mm strap takes a 22 mm buckle, or 24/22.

This measurement matters little when ordering: our straps are supplied with their original buckle. It becomes useful only if you wish to reuse your current buckle — in which case measure it precisely beforehand.

The length

A standard strap is around 20 cm in total: an 8 cm short section and a 12 cm long section. This length suits the vast majority of wrists.

Other formats exist across the ranges: Medium at 18 cm for slim wrists, XL at 22 cm for larger wrists or for wearing over a sleeve.

Attachment systems: spring bars and Quick Release

Spring bars

Straps are attached to the watch by spring bars, metal rods housed between the lugs. Always choose marine-grade stainless steel: ordinary steel oxidises and eventually seizes.

Check their condition every time you change strap — bent, seized or pitted, they must be replaced. A tired spring bar that gives way means a watch on the floor.

New strap = new spring bars

The standard diameter is 1.5 mm. We recommend 1.8 mm stainless steel, more robust, particularly on NATO straps where the entire load rests on the bars. The length matches the lug width: a 20 mm watch takes 20 mm spring bars.

20mm lug width measurement for spring bars

Set of 4 reinforced 20 mm stainless steel spring bars

The Quick Release system

Some straps include a quick-release fitting. A small stainless steel tab, operated with a fingernail, compresses the spring bar and frees the strap without any tool. The Hirsch range now fits this system to most of its models, with robust, well-finished bars.

One important caveat, and it concerns measurement: the size must be exact. A 20 mm Quick Release strap fits correctly only on a lug width of precisely 20 mm. If your watch measures 21 mm, the attachment will not hold.

In that case there is a solution: carefully remove the tab with pliers, take out the bar, and replace it with a standard stainless steel spring bar of the right size. The strap becomes compatible again.

To see the operation in real conditions, our video guide covers removal on every type of attachment: removing a watch strap.

Changing a strap: removal and fitting

Removing a strap requires a fine-forked tool. Never use a screwdriver: the flat blade slips and scratches the lugs, and this is the single most common cause of damage to a case.

Be wary too of cheap tools sold for a few euros. Poor-quality steel breaks quickly, and a fork that is too thick damages the strap as much as the watch. The professional reference remains the Bergeon 6767F tool, made in Switzerland, whose stainless fork is both very fine and durable.

The operation takes only a few movements: place the watch face down on a soft surface, slide the fork between the strap and the lug, hook the spring bar, compress it until it releases, then swing the strap clear. The technique varies depending on whether your lugs are drilled — the tool enters from the outside — or solid, where the bar is reached from the inside.

Our detailed guides cover every configuration on video: removing a watch strap for removal, and fitting a NATO strap for installation.

Materials: leather, rubber, nylon

The material transforms the look of a watch as much as its colour. It also determines how long the strap lasts and how comfortable it feels. Here is what genuinely sets the families apart.

Tanning, the first mark of quality

Before the material comes the process. Entry-level straps use chrome-tanned leather: stiff, short-lived, and a source of allergies in contact with the skin.

Vegetable tanning, used by Hirsch and Arezzo, uses no chemicals but tree barks — oak chiefly, one of the richest in tannins. Drummed for several months, the hides remain naturally hypoallergenic. The resulting leather is more supple, and the pigments used are natural too.

It is an old process, longer and more costly. It is also what separates a strap that ages well from one that hardens within six months.

Classic leathers and nubuck

Calf, veal, buffalo: standard leathers are built from bonded then stitched layers. The lining must be hypoallergenic. Structures are either padded — a water-repellent foam rounded beneath the surface layer — or flat, depending on the style.

The edge finish distinguishes two schools. Turned edge, where the surface wraps around the edges and folds underneath: the classic, padded register. Cut edge, where the stacked layers are cut vertically then brush-sealed with a thin latex coating against moisture — often paired with vintage Italian stitching.

cross section of a watch strap turned edge and cut edge

Nubuck is obtained by sanding the surface of a calf or buffalo hide. Velvety to the touch, matt and warm in appearance, fine and light in structure. It softens a steel case like no other material. Two references from the range: the Hirsch Osiris, nubuck surface with smooth leather lining, and the Arezzo Nubuck Slim, vegetable-tanned on both faces.

Embossed and precious leathers

An embossed leather is a calf hide press-stamped with a scale pattern. The imitation of alligator is striking, especially with a coloured patina — and the price remains that of a classic strap. The two flagship models of the Hirsch range: the Duke gold brown and the Grand Duke black waterproof with red stitching, available from 18 to 24 mm.

hirsch duke gold brown alligator embossed strap

hirsch grand duke black red stitching strap

Genuine precious leathers — ostrich, lizard, crocodile, alligator — are imported under strict CITES control. They are superb, but more fragile than a classic leather.

Knowing how to recognise them protects against counterfeits. A genuine ostrich hide shows only a few raised points on the surface, the quill follicles. Crocodile has slightly rounded scales, alligator has square scales, and alligator flank has perfectly circular ones. Farmed crocodile remains considerably cheaper than Mississippi alligator.

Two examples available in our shop: the Hirsch Capitano Alligator black waterproof and the Arezzo Dark-Croco honey, rubber-lined, both in 20 and 22 mm.

Waterproof leathers and technical ranges

Some leathers undergo an oil-enriched tanning that makes them water-resistant. The most technical versions add a rubber lining and specific bonding to guarantee water resistance. Longer life, sporty look — the surface is often carbon-embossed, as on the Hirsch Carbon orange or the Arezzo Racing.

hirsch carbon orange waterproof watch strap

arezzo racing carbon blue stitching watch strap

The Hirsch Performance range takes the principle further: a genuine rubber core covered with classic or precious leather, with a patented grid pattern on the rubber section that promotes drying and channels perspiration away. Waterproof, sauna-resistant, water-resistant to 300 m. Two representative references: the Hirsch James gold brown and the Hirsch Robby in red and black.

Beware of imitations: many websites offer a similar look on a silicone base with cheap leather bonded on top. The appearance is there, the engineering is not.

hirsch james performance leather rubber strap

hirsch robby red rubber black leather strap

Rubber: natural or synthetic

The distinction is decisive. Rubber belongs to the elastomer family. Natural rubber comes from the latex of the hevea tree; synthetic rubber is derived from hydrocarbons or silicon.

Genuine rubber costs more, but it resists traction and tearing, withstands heat, and feels far more pleasant than polyurethane or silicone. It is manufactured in Europe.

Synthetic appeals through its price and its endless range of colours, but its excessive softness makes it unsuitable for technical use, and it eventually cracks. It is the material of imported elastic straps.

The benchmark in this category remains the Hirsch Pure in black rubber, also available in orange and blue.

Discover the rubber straps

NATO and rally straps

The NATO strap is a single piece of woven nylon, passing right under the case. Its safety comes from that: if one spring bar gives way, the watch is still held by the second pass. It changes in fifteen seconds, resists water and can be machine washed.

Its history and uses are covered in our dossier: the history of the NATO strap.

The rally strap, pierced with three holes or more, was designed for chronographs. It lightens the wrist, ventilates, and pairs naturally with a Speedmaster or any three-register watch. Two Arezzo models: the Monza three-hole, the more vintage of the two, and the Maranello multi-hole, in smooth or suede leather.

arezzo maranello rally watch strap honey leather

Matching colours

The same watch changes character entirely depending on its strap — provided the pairing works. Several criteria come into play: the age of the watch, the thickness of the case, the colour of the dial and hands, and your own dress style.

The same Omega Speedmaster, same camera angle, four straps from €19 to €299.

arezzo monza rally strap on omega speedmaster

arezzo crocodile watch strap on speedmaster

arezzo dark croco crocodile strap on speedmaster

The basic rule is to match the strap to the dial or the hands.

On an older watch, with patinated indices and hands, avoid stitching that is too white: it hardens the whole. Prefer a strap with no visible stitching, or tone-on-tone stitching. Black leather works equally well with a light or dark dial; the same is true of brown and beige. Navy blue, on the other hand, sits poorly with older gold-tone watches.

On a modern watch, indices and hands are bright, steel or painted. Visible stitching can then echo the hands. Red stitching works well provided something on the dial picks it up — an inscription, or at the very least the seconds hand.

Pin buckle or deployant clasp?

Pin buckles

The pin buckle works on the same principle as a belt buckle: the holes in the long section allow precise adjustment. All our straps are fitted with one as standard, generally in silver-tone stainless steel, also available in gold tone.

Pins are slim, suited to small adjustment holes. Some sports straps use wide pins, which require enlarged oval holes — the GPF style found on Panerai or Bell & Ross.

Deployant clasps

Two families exist. The basic V-shaped deployant, single-hinged, clips shut under pressure. The butterfly deployant, in three parts with two hinges, includes a mechanical lock: it opens only when both side buttons are pressed simultaneously.

Take care with the original clasps of certain brands. So-called standard deployants use the strap's adjustment holes: the strap therefore remains interchangeable. Others, notably at Breitling, clamp the strap to adjust its length — in which case your new strap will need to be exactly the same thickness.

Fitting a deployant clasp to a standard strap

The operation is simple. Take the example of a 20 mm strap bought from our shop: its exact size is 20/18, meaning 20 mm at the lugs and 18 mm at the buckle. You therefore need an 18 mm deployant clasp to replace the original pin buckle.

Discover the deployant clasps

Lug width by brand: find the right strap size

The lug width is the gap between the two lugs of your watch, in millimetres. It is this measurement, and not the case diameter, that determines the strap width to choose. Find your watch below; if in doubt, measure the gap between your lugs before ordering.

Watch models and lug width in millimetres
Brand	Model	Lug width	Type
A. Lange & Sohne	Lange 1	20 mm	Dress
	Saxonia	20 mm	Dress
Audemars Piguet	Code 11.59	22 mm	Dress
	Royal Oak	integrated†	Sport
Baume & Mercier	Classima 31 dame	16 mm	Dress
	Clifton	20 mm	Dress
Bell & Ross	BR V2-94	22 mm	Sport
	BR01	24 mm	Sport
	BR03	24 mm	Sport
Blancpain	Fifty Fathoms 42	22 mm	Dive
Breitling	Premier 40	20 mm	Sport
	Chronomat B01 42	22 mm	Sport
	Colt	22 mm	Pilot
	Navitimer 41	22 mm	Pilot
	Navitimer 43	22 mm	Pilot
	Premier B01 Chronograph 42	22 mm	Chronograph
	SuperOcean Heritage	22 mm	Pilot
	Top Time	22 mm	Chronograph
Bremont	Supermarine	22 mm	Sport
CWC	G10	18 mm	Field
	RN Diver	20 mm	Dive
	SBS Diver	20 mm	Dive
Cartier	Tank Louis Small	16 mm	Dress
	Tank Louis	19 mm	Dress
	Tank Must	19 mm	Dress
	Ballon Bleu 40	20 mm†	Sport
	Ronde	20 mm	Dress
	Santos	integrated†	Sport
	Tank Française Small	integrated†	Dress
Certina	DS-1 Small	20 mm	Dress
Chopard	L.U.C	20 mm	Dress
Citizen	Chandler	18 mm	Field
	NB1050	19 mm	Sport
	Fujitsubo	20 mm	Dive
	Promaster Diver	20 mm	Dive
	Promaster Eco-Drive	22 mm	Dive
	Aqualand	24 mm	Dive
	Promaster 1000 m	29 mm†	Dive
Doxa	Sub 200	20 mm	Dive
	Sub 300	20 mm	Dive
Fortis	B42	20 mm	Pilot
Frederique Constant	Slimline Dame	16 mm	Dress
	Slimline 37	18 mm	Dress
	Classics	20 mm	Dress
	Slimline	20 mm	Dress
Glashutte Original	Senator	20 mm	Dress
Grand Seiko	Elegance	19 mm	Sport
	SBGW231	19 mm	Sport
	SBGA211 Snowflake	22 mm	Sport
	Spring Drive Chronograph	23 mm	Chronograph
Hamilton	American Classic Boulton	18 mm	Dress
	Intra-Matic 34	18 mm	Dress
	Khaki Pilot Pioneer	18 mm	Pilot
	Intra-Matic	19 mm	Dress
	Jazzmaster	20 mm	Dress
	Khaki Aviation	20 mm	Pilot
	Khaki Field Auto	20 mm	Field
	Khaki Field Mechanical 38	20 mm	Field
	Jazzmaster Auto Chrono	22 mm	Chronograph
	Khaki Aviation Converter	22 mm	Pilot
	Khaki Navy Frogman	22 mm	Dive
IWC	Mark XVIII	20 mm	Pilot
	Mark XX	20 mm	Pilot
	Pilot Mark XVIII	20 mm	Pilot
	Portofino 40	20 mm	Dress
	Portugieser 40.4	20 mm	Pilot
	Portugieser Chronograph	20 mm	Pilot
	Big Pilot 43	21 mm	Pilot
	Big Pilot 46	22 mm	Pilot
	Portugieser 42	22 mm	Pilot
	Ingenieur (2023)	integrated†	Sport
Jaeger-LeCoultre	Reverso	20 mm	Dress
	Master Control	21 mm	Dress
	Master Ultra Thin	21 mm	Dress
Junghans	Max Bill Handaufzug 34	18 mm	Dress
	Max Bill	20 mm	Dress
Longines	Conquest Heritage 35	18 mm	Dress
	DolceVita dame	18 mm†	Dress
	Flagship Heritage	19 mm	Dress
	Heritage Classic	19 mm	Dress
	HydroConquest 39	19 mm	Sport
	Presence	19 mm	Dress
	Présence 38.5	19 mm	Dress
	Spirit 37	19 mm	Sport
	Avigation BigEye	20 mm	Pilot
	DolceVita	20 mm	Dress
	Legend Diver 39	20 mm	Dive
	Master Collection	20 mm	Dress
	Master Chronograph	21 mm	Chronograph
	Spirit 40	21 mm	Sport
	Spirit Zulu Time 39	21 mm	Sport
	La Grande Classique	integrated†	Sport
Luminox	Navy SEAL	23 mm	Dive
Marathon	General Purpose	16 mm	Field
	GSAR	20 mm	Dive
	TSAR	20 mm	Dive
	JSAR	22 mm	Dive
	Jumbo Diver	22 mm	Dive
Mido	Baroncelli III	20 mm	Dress
Montblanc	1858 Automatic	20 mm	Dress
	Heritage	20 mm	Dress
	1858 Geosphere	22 mm	Dress
Nomos	Ludwig 33	17 mm	Sport
	Orion 35	18 mm	Dress
	Tangente 35	18 mm	Dress
	Orion	19 mm	Dress
	Club	20 mm	Dress
	Tangente 38	20 mm	Dress
Omega	30t2	18 mm	Sport
	De Ville vintage	18 mm	Dress
	Genève vintage	18 mm	Sport
	Seamaster Vintage 34	18 mm	Dive
	Constellation	19 mm†	Sport
	De Ville Prestige	19 mm	Dress
	Seamaster Aqua Terra 38	19 mm	Dive
	Aqua Terra 38	20 mm	Sport
	Aqua Terra 41	20 mm	Sport
	De Ville Tresor	20 mm	Dress
	Globemaster	20 mm	Dress
	Railmaster 40	20 mm	Sport
	Seamaster 300 Heritage	20 mm	Dive
	Seamaster Aqua Terra 41	20 mm	Dive
	Seamaster Diver 300M	20 mm	Dive
	Speedmaster Professional Moonwatch	20 mm	Chronograph
	Planet Ocean 42	21 mm	Sport
	Planet Ocean XL	22 mm	Sport
Oris	Artelier Date 34	16 mm	Dress
	Big Crown Pointer Date	20 mm	Sport
	Big Crown ProPilot 41	20 mm	Pilot
	Artelier	21 mm	Dress
	Aquis 43	24 mm†	Dive
	ProDiver	26 mm	Dive
Panerai	Luminor Due 42	22 mm	Sport
	Luminor Marina 42	22 mm	Sport
	Luminor Marina 44	24 mm	Sport
	PAM000	24 mm	Sport
	PAM005	24 mm	Sport
	PAM111	24 mm	Sport
	PAM112	24 mm	Sport
	PAM176	24 mm	Sport
	PAM177	24 mm	Sport
	PAM312	24 mm	Sport
	PAM320	24 mm	Sport
	PAM392	24 mm	Sport
	Radiomir 45	24 mm	Sport
	Submersible 44	24 mm	Dive
	Egiziano	26 mm	Sport
	PAM305	26 mm	Sport
	PAM372	26 mm	Sport
	PAM389	26 mm	Sport
	PAM422	26 mm	Sport
	PAM423	26 mm	Sport
	PAM424	26 mm	Sport
	PAM507	26 mm	Sport
	Radiomir 47	26 mm	Sport
Patek Philippe	Calatrava	20 mm	Dress
	Aquanaut	integrated†	Sport
	Nautilus	integrated†	Sport
Piaget	Altiplano	21 mm	Dress
Rado	Coupole dame	integrated†	Sport
Raymond Weil	Toccata	20 mm	Dress
Rolex	Lady-Datejust 28	13 mm†	Dress
	Datejust 31	14 mm	Dress
	Air-King 5500	19 mm	Sport
	Date 1500	19 mm	Sport
	Oyster Perpetual 34	19 mm	Dress
	1908 39	20 mm	Dress
	Air-King 126900	20 mm	Sport
	Cellini	20 mm	Dress
	Datejust 36	20 mm	Dress
	Day-Date 36	20 mm	Dress
	Day-Date 40	20 mm	Dress
	Daytona 40	20 mm	Chronograph
	Explorer 114270	20 mm	Field
	Explorer 14270	20 mm	Field
	Explorer 36	20 mm	Field
	Explorer II	20 mm	Field
	GMT-Master 1675	20 mm	Sport
	GMT-Master II	20 mm	Sport
	Milgauss	20 mm	Sport
	Oyster Perpetual 36	20 mm	Dress
	Sea-Dweller 16600	20 mm	Dive
	Submariner 14060	20 mm	Dive
	Submariner 16610	20 mm	Dive
	Submariner 5513	20 mm	Dive
	Yacht-Master 40	20 mm	Sport
	Datejust 41	21 mm	Dress
	Deepsea Sea-Dweller	22 mm	Dive
	Deepsea Challenge	23 mm	Dive
Seiko	SNK809	18 mm	Field
	SNXS79	18 mm	Field
	Alpinist	20 mm	Sport
	Monster	20 mm	Dive
	Presage Cocktail SRPB43	20 mm	Dress
	SPB143	20 mm	Sport
	SPB147	20 mm	Sport
	SPB151	20 mm	Sport
	SPB153	20 mm	Sport
	Sumo	20 mm	Sport
	Arnie	22 mm	Sport
	SKX007	22 mm	Dive
	SKX009	22 mm	Dive
	Samurai	22 mm	Dive
	Tuna Professional	22 mm	Dive
	Turtle King	22 mm	Dive
Sinn	104	20 mm	Sport
	556	20 mm	Sport
	856	20 mm	Sport
	857	22 mm	Sport
	U1	22 mm	Dive
	U2	22 mm	Dive
Squale	1521	20 mm	Dive
TAG Heuer	Carrera 42	20 mm	Chronograph
	Monaco	22 mm	Chronograph
Timex	Expedition Scout	20 mm	Field
Tissot	PRX 35	integrated†	Sport
	Le Locle 25 dame	14 mm	Dress
	Bellissima	16 mm	Dress
	Everytime Small	16 mm	Dress
	Le Locle	19 mm	Dress
	Carson	20 mm	Dress
	Visodate	20 mm	Dress
	Gentleman	21 mm	Sport
Tudor	1926 28	15 mm	Dress
	1926 36	19 mm	Dress
	Prince Date 34	19 mm	Sport
	Black Bay 54	20 mm	Dive
	Black Bay 58	20 mm	Dive
	Glamour Date	20 mm	Dress
	Ranger	20 mm	Field
	1926 39	21 mm	Dress
	Pelagos 39	21 mm	Dive
	1926 41	22 mm	Dress
	Black Bay Chrono	22 mm	Dive
	Black Bay Pro	22 mm	Dive
	Pelagos 42	22 mm	Dive
	Royal	22 mm†	Sport
U-Boat	Classico	22 mm	Sport
Vacheron Constantin	Patrimony	20 mm	Dress
	Traditionnelle	20 mm	Dress
	Overseas	integrated†	Sport
Zenith	Chronomaster Original	19 mm	Sport
	Elite	20 mm	Dress
	Pilot Type 20	22 mm	Pilot
	Defy Skyline	integrated†	Sport

† Watch with an integrated bracelet or proprietary fitting: a standard spring-bar strap will not fit directly, a specific strap is required.
Indicative list of 245 references. The same watch may exist in several case sizes with different lug widths — check yours if in doubt.

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FAQ — Watch strap size and dimensions

How do I measure the size of a watch strap?

Measure the lug width, that is the gap between the two lugs of the case, with a vernier caliper or a ruler. This measurement in millimetres corresponds directly to the strap width to order. Do not measure your old strap, which may be deformed or wrongly sized.

What is the difference between lug width and strap width?

None: they are two ways of naming the same measurement. Lug width refers to the gap between the lugs on the watch side; strap width is that of its attachment end. The two must be identical.

What strap length suits my wrist size?

A standard 20 cm strap suits wrists from 16 to 20 cm. Below that, choose a Medium length at 18 cm. Above, or for wearing over clothing, choose an XL length at 22 cm.

My lug width is 21 mm: what can I fit?

Straps in 19 and 21 mm exist but remain uncommon. On a 21 mm lug width, a 20 mm strap fits with a visible gap; a 22 mm one will not go in. Avoid Quick Release straps, however, as they require an exact size.

How do I know whether my watch takes a standard strap?

Look between the lugs: if you can see a removable spring bar, your watch takes a standard strap. Watches with an integrated bracelet or a proprietary fitting — Royal Oak, Nautilus, Overseas, certain PRX models — require a strap specific to the brand.

What spring bar size for a 20 mm lug width?

20 mm spring bars: the length of the bar always matches the lug width. For the diameter, choose 1.8 mm stainless steel rather than the standard 1.5 mm, particularly on a NATO strap.