Prospex Sumo SPB321J1 45mm

How it wears

Wears true to its 45 mm case size

Seiko Prospex Sumo SPB321J1 45mm measures 52 mm lug-to-lug on a 45 mm case, a lug-to-lug ratio of 1.16 against a database median of 1.18. That span is longer than 94% of the 7,413 watches in this database and longer than 98% of the 390 Seiko watches listed.

A flat wrist width of 58 mm (2.28 in) or more keeps it in the balanced range, and from 70 mm (2.76 in) it starts to look compact. Below 52 mm (2.05 in) the lugs are likely to overhang the wrist. Flat wrist width is measured straight across the top of the wrist, not around it.