San Martin · Factory brand · China

San Martin SN054 39mm (NH34)

Ref. SN0054-G-C · In production · GMT

Design reference: Tudor Black Bay Pro

San Martin SN0054-G-C 39mm NH34 GMT with black dial and date at 3 on bracelet
Photo: San Martin
  • San Martin SN0054-G-C 39mm NH34 GMT with white dial and date at 3 on bracelet
  • San Martin SN0054-G-C 39mm NH34 GMT with orange dial and date at 3 on bracelet
  • San Martin SN0054-G-C 39mm NH34 GMT with green dial and date at 3 on bracelet
  • San Martin SN0054-G-C 39mm NH34 GMT with blue dial and date at 3 on bracelet
  • San Martin SN0054-G-C2 39mm NH34 GMT with pink dial and date at 3 on bracelet
  • San Martin SN0054-G-C2 39mm NH34 GMT with orange dial and date at 3 on bracelet
  • San Martin SN0054-G-B1 39mm NH34 GMT with black dial and date at 3 on bracelet
  • San Martin SN0054-G-B1 39mm NH34 GMT with white dial and date at 3 on bracelet
  • San Martin SN0054-G-B1, side view showing case profile
  • San Martin SN0054-G-C lume shot
From $299 to $370
  • Seiko NH34A
  • 40 mm × 12.4 mm
  • Sapphire crystal
  • 100 m water resistance

Movement

Type
Automatic
Tier
Entry
Complications
Date, GMT
Frequency
21,600 bph
Power reserve
41 h
Hacking
Yes
Accuracy (factory)
-20 / +40 s/day

Case

Diameter
40 mm
Lug to lug
48.5 mm
Thickness
12.4 mm
Lug width
20 mm
Material
Steel (316L)
Hardening
—
Water resistance
100 m
Crown
Screw-down
Case back
—
Bezel
24-hour GMT
Finishing
Brushed caseback

Crystal & dial

Crystal
Sapphire
Shape
Box
Anti-reflective
Yes (side not stated)
Lume
BGW-9

Bracelet & clasp

Style
Oyster
Links per row
3
Solid end links
—
Solid links
Yes
Link attachment
—
Taper
20 → 16 mm
Quick release
—
Half links
—
Clasp
Fold-over
Micro-adjust
—
Diver extension
—

Weight

Head only
—
On bracelet
—
On strap
—
Stated weight (basis not given)
141 g

Prices

VariantConfigurationTypePriceUSDAs ofSource
C black dial—Street370 USD$3702026-10-24link
C white dial—Street370 USD$3702026-10-24link
C orange dial—Street370 USD$3702026-10-24link
C green dial—Street370 USD$3702026-10-24link
C blue dial—Street370 USD$3702026-10-24link
C2 pink dial—Street309 USD$3092026-10-24link
C2 orange dial—Street309 USD$3092026-10-24link
B1 matte black dial—Street299 USD$2992026-10-24link
B1 matte white dial—Street299 USD$2992026-10-24link

Variants

NameReferenceDial
C black dialSN0054-G-Cblack
C white dialSN0054-G-Cwhite
C orange dialSN0054-G-Corange
C green dialSN0054-G-Cgreen
C blue dialSN0054-G-Cblue
C2 pink dialSN0054-G-C2pink
C2 orange dialSN0054-G-C2orange
B1 matte black dialSN0054-G-B1black
B1 matte white dialSN0054-G-B1white

About this entry

79% of key specs known. Missing: hardening, end links, link attachment, clasp micro-adjust.

The SN054 (the brand writes SN0054; store category SN054) 39mm GMT with a Seiko NH34, styled after the Tudor Black Bay Pro ("BB GMT" in the titles). Three listings of the same case are merged here: the SN0054-G-C ($370; black, white, orange, green or blue; applied logo and indices; about 141g; "quick-adjust" folding clasp with safety), the SN0054-G-C2 ($309; pink or orange; filed under Pre-Order Model; about 141g; same quick-adjust clasp) and the SN0054-G-B1 ($299; matte black or white, with or without logo at the same price; 143g; folding clasp with safety and 4 micro-adjust holes). The B1 and C give 12.4mm thick and the C2 12.8mm; San Martin hand-measures and the case is otherwise the same, so 12.4mm is recorded (not stated whether that includes the crystal). Shared brand specs: 316L, 39mm case with a 40mm bezel (diameter_mm records the larger figure, per the data guide), 48.5mm lug-to-lug, 20mm lugs, "top hat" sapphire with AR coating (side not stated; recorded as a box shape), 316L bezel with an engraved 24-hour scale (whether it rotates is not stated), snowflake hands with a GMT hand, BGW-9 lume on hands and markers, date window, screw-down crown with 3D hexagon logo, brushed screw-down caseback, solid 316L bracelet 20mm tapering to 16mm, 100m. Weight is the C's 141g (not stated what was weighed). Micro-adjust is left blank because the B1 clasp has 4 holes and the C and C2 use a "quick-adjust" clasp the listings don't describe further. Bracelet style and link count are taken from the photos (three-link oyster style). The C's orange and green dials were in stock on 2026-10-25; every other variation showed "Out of stock". The Hangzhou 6460 versions of this case (48.3mm lug-to-lug, 13mm) are in sn054-hangzhou-6460. Inspired_by is read from the design (engraved steel 24-hour bezel, snowflake hands) and the "BB GMT" titles; the brand does not name the Tudor.

Last verified: 2026-10-25. Edit or correct this entry.

Sources