Prospex Mechanical 39.5mm

How it wears

Wears true to its 39.5 mm case size

Seiko Prospex Mechanical 39.5mm measures 46.4 mm lug-to-lug on a 39.5 mm case, a lug-to-lug ratio of 1.17 against a database median of 1.18. That span is shorter than 57% of the 7,413 watches in this database and shorter than 44% of the 390 Seiko watches listed.

A flat wrist width of 52 mm (2.05 in) or more keeps it in the balanced range, and from 62 mm (2.44 in) it starts to look compact. Below 46.4 mm (1.83 in) the lugs are likely to overhang the wrist. Flat wrist width is measured straight across the top of the wrist, not around it.

At 12.7 mm thick it sits within the typical range, thicker than 57% of the watches with a listed thickness.