What size strap does a San Martin watch take?

For the great majority of San Martin references the answer is 20mm. Across the current European store catalog, 97 of 119 standard-strap watches take 20mm at the lugs. The dress class goes narrower (SN0102 18mm, SN0118 18mm, SN0055 18mm on a 42mm case), three families use the odd 19mm width (SN0021-G-B2, SN0108, JH0601), a handful of big cases take 21mm (SN0130 GMT, SN0065, SN0132, the 42mm SN0144) and the biggest standard cases take 22mm (SN0125-T, SN0046-G, SN0029-G-B, the JIANGHUN JH0201/JH0202 chronographs). Every figure comes from the Lug width field the official stores print per reference.

Do San Martin bracelets taper, and by how much?

Yes, and the official Chinese store prints the taper in the spec blob as two numbers, for example Bracelet 7 links 316L, 20mm*16mm. The convention on 20mm watches is a taper to 16mm at the clasp, verified on SN0116-G GMT, SN0116-G-B, SN0128-G, SN0053-G, SN0054 families, SN0058-G-X and SN0142-G; some bracelets taper only to 18mm (SN0007-G-JS class). The Y-shape bracelet of the SN0146 goes 26mm to 18mm. Aftermarket strap makers usually sell 20/16 as the San Martin fit, which matches the factory taper.

Which San Martin watches do not take standard straps at all?

The integrated-bracelet models: SN0074, SN0075 and SN0076 (13mm mount), SN0145-G (24mm barrel case), SN0146-G (26mm Y-shape bracelet), SN0148-GB (10.2mm end link), SN0149-G (25.5mm) and SN0152-G (24mm waffle dial). These have no 18/20/22mm spring-bar gap; the bracelet is part of the case design. If you own one of these and want a different strap, you need the brand's own spare parts, not a standard replacement band.

Is the San Martin SN0144 a 19mm, 20mm or 21mm watch?

All three, depending on the case. SN0144 is one design scaled across three sizes, and the official spec tables move the lug width with the case: 36mm case (SN0144-GS) takes 19mm, 39mm case (CG, GX and most variants) takes 20mm, and the 42mm SN0144-GL takes 21mm. Lug-to-lug scales from 43.5 to 49.5mm across the set. Check the case size on your caseback before ordering, not the family name.

San Martin band size chart by SN reference

San Martin runs two official stores, and both print the numbers this chart needs. The European store (san-martin.com) carries a Lug width field in every product spec table ^[3]; the official Chinese store (sanmartinwatches.com) prints Lug to lug width inside the description spec blob on its newer pages ^[1]. Pulled fresh at build time, the two rails agree on every reference they share. The headline: San Martin is a 20mm brand with exceptions worth knowing before you order, because the family name alone will not tell you the width ^[6]. This chart covers 80 SN and JIANGHUN families, 119 standard-strap references and 9 integrated-bracelet models.

Quick answers: most San Martin watches take 20mm straps. Dress class is narrower: SN0102 18mm, SN0118 18mm, SN0137 18mm, and the 42mm SN0055 on an 18mm leather band. Odd 19mm: SN0021-G-B2, SN0108, JH0601. Odd 21mm: SN0130 GMT, SN0065, SN0132, 42mm SN0144-GL. Big-case 22mm: SN0125-T, SN0046-G, SN0029-G-B, JH0201/JH0202. The SN0144 family scales 19/20/21mm with its 36/39/42mm cases. SN0074/75/76, SN0145, SN0146, SN0148-GB, SN0149 and SN0152 have integrated bracelets and take no standard strap at all.

How to read San Martin specs

On san-martin.com, open the product page and read the spec table: Lug width is printed in millimetres next to Case diameter and Lug-to-lug ^[5]. On sanmartinwatches.com the spec blob in the description reads Lug to lug width 20 mm ^[1] ^[2]. The two stores sometimes list different reference variants, but on the 11 families both carry, the widths match exactly. Bracelet taper, when published, appears only on the Chinese store, as a 20mm*16mm pattern inside the bracelet line ^[9]. If your watch disagrees with any row below, measure the gap as shown in our lug width chart before ordering.

The chart: 80 families, 119 standard references

SN family	Case	Lug width	Lug to lug	Bracelet taper	Notes
JH0102 (1 ref)	42mm	20mm	49mm		20mm, the San Martin default
JH0104 (1 ref)	42mm	20mm	49.86mm		20mm, the San Martin default
JH0105 (1 ref)	46mm	22mm	52.5mm		22mm big-case class ^[24]
JH0106 (1 ref)	42mm	20mm	48.55mm		20mm, the San Martin default
JH0107 (1 ref)	42mm	20mm	48.55mm		20mm, the San Martin default
JH0201 (1 ref)	42mm	22mm	49mm		22mm big-case class ^[24]
JH0202 (1 ref)	42mm	22mm	49mm		22mm big-case class ^[24]
JH0301 (1 ref)	39mm	20mm	46.5mm		20mm, the San Martin default
JH0401 (1 ref)	37mm	20mm	46.5mm		20mm, the San Martin default
JH0402 (1 ref)	37mm	20mm	46.5mm		20mm, the San Martin default
JH0403 (1 ref)	37mm	20mm	46.5mm		20mm, the San Martin default
JH0601 (1 ref)	-	19mm	43mm		19mm odd width
SN0004 (1 ref)	38mm	20mm	46mm		20mm, the San Martin default
SN004 (1 ref)	38mm	20mm	46mm		20mm, the San Martin default
SN0005 (1 ref)	40mm	20mm	48.5mm		20mm, the San Martin default
SN0007 (4 refs)	37, 40, 41mm	20mm	46.5, 48, 50mm		20mm, the San Martin default
SN0008 (2 refs)	40mm	20mm	48, 49.5mm		20mm, the San Martin default
SN0009 (1 ref)	40mm	20mm	46.5mm		20mm, the San Martin default
SN0012 (1 ref)	40mm	20mm	48.5mm		20mm, the San Martin default
SN0013 (1 ref)	38.5mm	20mm	48mm		20mm, the San Martin default
SN0017 (1 ref)	40mm	20mm	48mm		20mm, the San Martin default
SN0020 (1 ref)	39mm	20mm	47.5mm		20mm, the San Martin default
SN0021 (3 refs)	36, 37mm	19, 20mm	45.5, 45.9mm		B2 is the 36mm/19mm variant; B1 and B3 are 37mm/20mm ^[12]
SN0022 (1 ref)	38mm	20mm	44.5mm		20mm, the San Martin default
SN0026 (2 refs)	38, 40mm	20mm	47mm		20mm, the San Martin default
SN0029 (3 refs)	38, 41mm	20, 22mm	47.5, 49mm		38mm case 20mm; the 41mm G-B jumps to 22mm ^[11]
SN0030 (1 ref)	39mm	20mm	49mm		20mm, the San Martin default
SN0031 (2 refs)	38mm	20mm	47.5mm		20mm, the San Martin default
SN0033 (1 ref)	39.5mm	20mm	48.1mm		20mm, the San Martin default
SN0034 (1 ref)	37mm	20mm	45.5mm		20mm, the San Martin default
SN0036 (1 ref)	41mm	20mm	48.5mm		20mm, the San Martin default
SN0044 (1 ref)	38.8mm	20mm	46.5mm		20mm, the San Martin default
SN0045 (1 ref)	40mm	20mm	43mm		20mm, the San Martin default
SN0046 (1 ref)	42.5mm	22mm	46.5mm		22mm big-case class ^[20]
SN0050 (1 ref)	38.5mm	20mm	47.2mm		20mm, the San Martin default
SN0053 (2 refs)	39mm	20mm	48.5mm	Bracelet tapers 20 to 16mm at the clasp	20mm, the San Martin default
SN0054 (3 refs)	39mm	20mm	48.5mm	Bracelet tapers 20 to 16mm at the clasp	20mm, the San Martin default
SN0055 (1 ref)	42mm	18mm	50mm		Narrow dress lug, rare at this case size42mm case on an 18mm leather band, the widest gap between case and width ^[14]
SN0058 (1 ref)	36.5mm	20mm	43mm	Bracelet tapers 20 to 16mm at the clasp	20mm, the San Martin default
SN0065 (1 ref)	40mm	21mm	48mm		21mm odd width ^[21]
SN0066 (1 ref)	42mm	20mm	46.5mm		20mm, the San Martin default
SN0067 (1 ref)	40mm	20mm	47mm		20mm, the San Martin default
SN0069 (1 ref)	40mm	20mm	46mm		20mm, the San Martin default
SN0074 (1 ref)	40mm	13mm	47.8mm
SN0075 (1 ref)	43mm	13mm	46.5mm
SN0076 (1 ref)	42mm	13mm	44mm
SN0085 (1 ref)	39.5mm	20mm	48mm		20mm, the San Martin default
SN0088 (1 ref)	41.5mm	20mm	49.5mm		20mm, the San Martin default
SN0095 (2 refs)	40, 44mm	20, 23mm	48, 54.2mm		Multiple widths inside one family, read the row for your case size
SN0101 (1 ref)	38mm	20mm	46.8mm		20mm, the San Martin default
SN0102 (1 ref)	37mm	18mm	42mm		Narrow dress lug, rare at this case size18mm dress class ^[3]
SN0105 (4 refs)	38.5mm	20mm	47.2mm		20mm, the San Martin default
SN0106 (1 ref)	37mm	20mm	45mm		20mm, the San Martin default
SN0108 (1 ref)	38.5mm	19mm	48.5mm		19mm odd width ^[22]
SN0110 (1 ref)	37mm	20mm	45mm		20mm, the San Martin default
SN0112 (2 refs)	38mm	20mm	46mm		20mm, the San Martin default
SN0116 (4 refs)	39.5mm	20mm	46.5mm	Bracelet tapers 20 to 16mm at the clasp <sup><a href="#src-9">[9]</a></sup>	20mm, the San Martin default
SN0118 (2 refs)	40mm	18mm	47.8, 48mm		Narrow dress lug, rare at this case size ^[13]
SN0125 (1 ref)	42mm	22mm	51.8mm		22mm big-case class ^[15]
SN0126 (1 ref)	38mm	20mm	46.5mm		20mm, the San Martin default
SN0128 (3 refs)	40mm	20mm	49.5mm	Bracelet tapers 20 to 16mm at the clasp	20mm, the San Martin default
SN0129 (6 refs)	39mm	20mm	46.5mm		20mm, the San Martin default
SN0130 (2 refs)	42mm	21mm	48.5mm		21mm odd width ^[16]
SN0132 (1 ref)	40mm	21mm	48mm		21mm odd width ^[23]
SN0133 (1 ref)	40mm	20mm	48.7mm		20mm, the San Martin default
SN0134 (1 ref)	40mm	20mm	48.7mm		20mm, the San Martin default
SN0135 (1 ref)	39mm	20mm	48.5mm		20mm, the San Martin default
SN0136 (1 ref)	39mm	20mm	47.5mm		20mm, the San Martin default
SN0137 (1 ref)	38mm	18mm	45mm		Narrow dress lug, rare at this case size18mm, narrowest width in the catalog ^[25]
SN0138 (1 ref)	37mm	20mm	45.8mm		20mm, the San Martin default
SN0142 (1 ref)	39.5mm	20mm	48.5mm	Bracelet tapers 20 to 16mm at the clasp	20mm, the San Martin default
SN0143 (1 ref)	40mm	20mm	46mm		20mm, the San Martin default
SN0144 (15 refs)	36, 39, 42mm	19, 20, 21mm	43.5, 46.5, 49.5mm		The scale family: 36mm case 19mm, 39mm 20mm, 42mm 21mm ^[6]
SN0145 (1 ref)	39.5mm	24mm	46.5mm
SN0146 (1 ref)	41mm	26mm	47.4mm
SN0148 (4 refs)	37.5, 40mm	10.2, 20mm	45, 46, 49.5mm		Standard SN0148s are 20mm; the GB integrated-bracelet version is its own system (see below)
SN0149 (1 ref)	40mm	25.5mm	44.7mm
SN0150 (2 refs)	39mm	20mm	46.5mm		20mm, the San Martin default
SN0151 (1 ref)	39mm	20mm	45mm		20mm, the San Martin default
SN0152 (1 ref)	39mm	24mm	44mm

The integrated-bracelet exceptions

These are the San Martin watches a standard replacement strap cannot serve. The mount width in the official spec tables is the bracelet end link, not a spring-bar gap, and the official site names the design: integrated bracelet ^[17]. Owners of these models change look by buying San Martin's own spare parts, not a 20mm strap from a strap maker.

Reference	Case	Mount width	What it is
SN0074-G	40mm	13mm	40mm case, 13mm mount: integrated-bracelet sports watch, standard straps do not fit ^[19]
SN0075-G-C	43mm	13mm	43mm case, 13mm mount: same integrated platform as SN0074 ^[19]
SN0076G	42mm	13mm	Integrated bracelet
SN0095-G-D	44mm	23mm	44mm case, 23mm lug width on a leather strap: the widest standard mount in the catalog
SN0145-G	39.5mm	24mm	39.5mm barrel-shaped dress case, 24mm integrated bracelet, no spring bars ^[8]
SN0146-G	41mm	26mm	41mm diver, 26mm Y-shape integrated bracelet tapering to 18mm at the clasp ^[7]
SN0148-GB	40mm	10.2mm	40mm integrated-bracelet diver, 10.2mm end-link mount ^[18]
SN0149-G	40mm	25.5mm	40mm luxury sports watch, 25.5mm integrated bracelet ^[17]
SN0152-G	39mm	24mm	40mm waffle-dial integrated bracelet, 24mm at the case ^[17]

San Martin's own straps: the 20mm ecosystem

The European store sells spare straps and bracelets as first-party products with the same Lug width field as the watches. The FKM rubber SF0010 is a 20mm strap, 195mm long ^[4]; the BD0128 beads-of-rice bracelet is 20mm tapering to 16mm, matching the factory bracelet taper convention; the BD0013 leather strap is 20mm. That the brand's whole spare-strap shelf speaks 20mm is the strongest confirmation of where the catalog centers ^[10].

Product	Lug width	Material	Length	Notes
BD0013	20mm	Leather	195mm	Leather strap, 20mm, fits 20mm SN cases
BD0128	20mm	Stainless Steel	195mm	316L beads-of-rice bracelet, 20mm tapering to 16mm, New Fly adjustable clasp
SF0010	20mm	Rubber	195mm	FKM rubber strap, 20mm lug width, 195mm length ^[4]

The traps, ranked by how often they catch buyers

Trap 1: assuming 20mm because it is a San Martin. True for 97 of 119 standard references, false for the dress class (SN0102, SN0118, SN0137, SN0055, all 18mm ^[3] ^[14]), the 19mm oddities (SN0021-G-B2, SN0108, JH0601 ^[22]), the 21mm big cases (SN0130 GMT, SN0065, SN0132 ^[16] ^[21] ^[23]) and the 22mm class (SN0125-T, SN0046-G, SN0029-G-B ^[15] ^[20] ^[11]).

Trap 2: the SN0144 family name. One design, three widths: 19mm at 36mm case, 20mm at 39mm, 21mm at 42mm ^[6]. The caseback tells you which row applies.

Trap 3: ordering a 20mm strap for an integrated model. SN0074 through SN0076, SN0145, SN0146, SN0148-GB, SN0149 and SN0152 have no standard spring-bar gap at all ^[19] ^[7]. The 13mm, 24mm, 25.5mm, 26mm and 10.2mm figures in their spec tables are bracelet mounts.

Trap 4: the 44mm SN0095-G-D. A 23mm lug width on a leather strap, the widest standard mount in the catalog; 22mm straps will not fit it.

Trap 5: JIANGHUN references. The JH-prefixed sister brand sells through the same stores with the same spec fields; JH0201 and JH0202 are 22mm chronographs ^[24] while JH0601 is a 19mm multi-case watch. The JH prefix does not change how you read the chart.

After the width: length and taper

San Martin band lengths run 175 to 220mm across the catalog, printed per reference in the same spec tables (190mm on the SN0102 dress watch ^[3], 195mm on the SN058 ^[5], 220mm on the SN0055 ^[14]). For strap length by wrist size, use our strap length chart. For what the second number in a 20/16 listing means, the watch strap taper guide covers the convention San Martin follows. Spring-bar tool advice for the swap itself is in our spring bar tool guide, and the Zelos band size chart covers the other big factory-direct microbrand name, whose 20/22 split by case size mirrors San Martin's with two lugless exceptions. The Baltany band size chart covers the other factory-direct homage house, whose 36mm class splits 18 and 20mm by model rather than by case.

For the other Hong Kong microbrand on the same shelf: the Phoibos band size chart charts all 81 current references from Phoibos's own Band lines, including the printed bracelet tapers San Martin's spec blocks do not carry.

Sources

San Martin official store (CN), SN044-G-SS product page: 38mm case, Lug to lug width 20mm, bracelet 20mm: sanmartinwatches.com
San Martin official store (CN), SN022-G product page: 38mm case, Lug to lug width 20mm: sanmartinwatches.com
San Martin official Europe store, SN0102-G spec table: Case diameter 37 mm, Lug width 18 mm, Band length 190 mm: san-martin.com
San Martin official Europe store, SF0010 FKM strap product: Lug width 20 mm, Band length 195 mm: san-martin.com
San Martin official Europe store, SN0058-G-X (Datejust homage) spec table: Lug width 20 mm, Lug-to-lug 43 mm: san-martin.com
San Martin official Europe store, SN0144 family pages (15 references): 36mm case 19mm, 39mm case 20mm, 42mm case 21mm lug width: san-martin.com
San Martin official store (CN), SN0146-G spec blob: 41mm case, Y-shape bracelet 26mm * 18mm: sanmartinwatches.com
San Martin official store (CN), SN0145-G spec blob: 39.5mm barrel case, solid integrated bracelet: sanmartinwatches.com
San Martin official store (CN), SN0116-G GMT spec blob: Bracelet 7 links 316L, 20mm*16mm: sanmartinwatches.com
San Martin official Europe store, SN0128-G BB diver homage spec table: Lug width 20 mm: san-martin.com
San Martin official Europe store, SN0029 family: 38mm case 20mm (G V2, G-C), 41mm case 22mm (G-B): san-martin.com
San Martin official Europe store, SN0021 family: B2 36mm case 19mm, B1/B3 37mm case 20mm: san-martin.com
San Martin official Europe store, SN0118 family: 40mm case with 18mm lug width: san-martin.com
San Martin official Europe store, SN0055-G spec table: 42mm case, 18mm lug width, 220mm leather band: san-martin.com
San Martin official Europe store, SN0125-T spec table: 42mm case, 22mm lug width: san-martin.com
San Martin official Europe store, SN0130-G-GMT spec table: 42mm case, 21mm lug width: san-martin.com
San Martin official website (sanmartin-watch.com), SN0152: 40mm Luxury Sport Waffle Dial Integrated Bracelet: www.sanmartin-watch.com
San Martin official website (sanmartin-watch.com), SN0148GB: 40mm Integrated Bracelet Diver Miyota 9015: www.sanmartin-watch.com
San Martin official website (sanmartin-watch.com) collections index: SN0074, SN0075, SN0076 integrated-bracelet sports watches: www.sanmartin-watch.com
San Martin official Europe store, SN0046-G spec table: 42.5mm case, 22mm lug width: san-martin.com
San Martin official Europe store, SN0065 spec table: 40mm case, 21mm lug width: san-martin.com
San Martin official Europe store, SN0108 spec table: 38.5mm case, 19mm lug width: san-martin.com
San Martin official Europe store, SN0132 spec table: 40mm case, 21mm lug width: san-martin.com
San Martin official Europe store, JIANGHUN JH0201/JH0202 (Chronograph homage) spec tables: 42mm case, 22mm lug width: san-martin.com
San Martin official Europe store, SN0137 spec table: 38mm case, 18mm lug width: san-martin.com