Table of Contents
Specs
| Spec | Value |
|---|---|
| Reference | SSK023K1 |
| Diameter | 39.4 mm |
| Height | 13.6 mm |
| Material | Stainless steel |
| Water resistance | 100 m |
| Crystal | Hardlex (curved) |
| Movement | 4R34 |
| Power reserve | 41 hours |
| Functions | Hours, minutes, seconds, GMT hand |
Background
The SSK023 is part of Seiko's 5 Sports GMT line, launched in 2023. It uses the 4R34 movement — a modified 4R36 with an independently adjustable GMT hand. The fixed bezel with 24-hour markings tracks a second timezone. At under €400, it's the cheapest mechanical GMT on the market from a major manufacturer. The "5" name references Seiko's five attributes of durability: shock resistance, water resistance, automatic winding, day-date display, and a recessed crown.