556 I

Ref. 556.010

Case diameter: 38.5 mm; Manufacturer spec
Lug-to-lug: 45.5 mm; Unverified
Thickness: 11 mm; Manufacturer spec
Lug width: 20 mm; Manufacturer spec

Retail price $1,490 (US, Oct 2026)

Your wristIdeal fit

Wrist flat: 55.1 mmLug-to-lug: 45.5 mm

How the 556 I wears

Its lugs add 7 mm to the 38.5 mm case, close to the 7.1 mm typical across the almanac, so its diameter is a fair guide to how it wears.

On our fit model it sits best on wrists from 6.5" to 7.5" (16.5–19.1 cm); below 6.5" the lugs start to reach the edge of the wrist.

At 11 mm thick it is slimmer than 61% of the 80 other everyday watches we've measured, so it slides under a cuff more easily than most.

Its 20 mm lug width is one of the most common strap sizes; 104 other watches here share it, so aftermarket straps are easy to find.

Will the 556 I fit your wrist?

With a 45.5 mm lug-to-lug, here is how it wears across common wrist sizes. We estimate the flat top of each wrist from its circumference; measure yours for a closer answer in the fit finder.

Wrist	Flat width (est.)	Fit
6"	47.2 mm	Snug, lugs near the edge
6.5"	51.2 mm	Ideal fit
7"	55.1 mm	Ideal fit
7.5"	59.1 mm	Ideal fit
8"	63 mm	Wears small

Specifications

Reference: 556.010
Collection: 556
Status: In production
Case material: stainless steel, satinized
Crystal: sapphire, AR
Water resistance: 200 m
Bezel: fixed
Dial: black
Strap / bracelet: leather strap (H-link bracelet option)
Weight: 65 g
Style: Everyday, Sport

Movement

Caliber: Sellita SW200-1
Type: automatic
Power reserve: 38 hours
Frequency: 28,800 vph (4 Hz)
Jewels: 26
Accuracy: -5/+12 s/day (Christopher Ward tolerance)

2 other watches use the Sellita SW200-1

Takes 20 mm straps. See other 20 mm watches and straps.

Watches that wear the same size

Other watches within 1.5 mm of its lug-to-lug.

Same 20 mm lug width

All 20 mm watches

These take the same straps as the 556 I.