It's actually quite interesting to see that the Marinemaster and Prospex Speedtimer 240Z designer wants a movement holding over five days of power reserve, packed into a case thinner than anything Seiko currently ships. Kawamura wants to keep that watch's rugged, simple proportions while optimizing materials for both lightness and strength. He aimed for a 38 mm diameter and under 11 mm of thickness. ⓘ Seiko - edited The newly released Seiko Prospex HBC010Then, he picked a thin bezel with smoother operability, Arabic numerals inlaid directly into the dial for durability (rather than printed or applied), a box-shaped curved sapphire crystal, and stronger magnetic resistance than current Marinemaster references have. Kawamura was answering a hypothetical, not previewing a real project, and nothing in the interview suggests Seiko has this watch in development.