Watch Almanac
Swatch

Sistem Boreal

Ref. YIS401GC

Case diameter
42 mm
Manufacturer spec
Lug-to-lug
50.6 mm
Manufacturer spec
Thickness
13.8 mm
Manufacturer spec
Lug width
—
Not published

Retail price $260 (US, Oct 2026)

Ideal fit
Wrist flat: 55.1 mmLug-to-lug: 50.6 mm

How the Sistem Boreal wears

Its lugs reach 8.6 mm past the 42 mm case, more than the 7 mm typical across the almanac, so it wears larger than its diameter suggests.

On our fit model it sits best on wrists from 7" to 8.5" (17.8–21.6 cm); below 7" the lugs start to reach the edge of the wrist.

At 13.8 mm thick it is thicker than 99% of the 166 other everyday watches we've measured, so expect it to sit tall on the wrist.

Will the Sistem Boreal fit your wrist?

With a 50.6 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.

WristFlat width (est.)Fit
6"47.2 mmLugs overhang
6.5"51.2 mmLugs overhang
7"55.1 mmIdeal fit
7.5"59.1 mmIdeal fit
8"63 mmIdeal fit

Specifications

Reference
YIS401GC
Collection
Sistem51 Irony
Status
In production
Case material
stainless steel
Crystal
polymer
Water resistance
30 m
Bezel
fixed stainless steel bezel
Dial
blue
Strap / bracelet
adjustable stainless steel bracelet, butterfly clasp
Style
Everyday

Movement

Caliber
Swatch Sistem51
Type
automatic
Power reserve
90 hours
Frequency
21,600 vph (3 Hz)
Jewels
19

Watches that wear the same size

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

Sources