Seiko Returns to Basics with the New Marinemaster SLA077 and SLA079

After experimenting with more compact versions in 2023, Seiko takes the Marinemaster back to its roots in 2024 with the new Prospex Marinemaster Diver 300m references SLA077 and SLA079. These models offer a larger case, higher water resistance, and the classic tool-watch style reminiscent of the original 2000 Marinemaster SBDX001, with influences from the 1968 diver.

The new stainless steel case measures 42.6mm, larger than the 2023 model’s 39.5mm but smaller than the original 44mm. The case is 13.4mm thick with a 49.3mm lug-to-lug length, offering a balance between robustness and comfort. The unidirectional black steel bezel features a 60-minute scale with a LumiBrite pearl at 12 o’clock. The familiar 4 o’clock screw-down crown and a double-domed sapphire crystal with anti-reflective coating on the inside ensure the watch’s 300-meter water resistance.

Two dial options are available: matte black (SLA079) and white (SLA077), both featuring large, LumiBrite-filled indices. The hour, minute, and lollipop-style seconds hands are also equipped with LumiBrite inserts. The date window sits between 4 and 5 o’clock, harmonizing with the dial’s color.

Inside, the in-house Seiko 8L35 automatic movement powers the watch. With 26 jewels, a 28,800vph (4Hz) beat rate, and a 50-hour power reserve, this movement provides accuracy within +15/-10 seconds per day. The bracelet and case both feature a hardened coating, and the steel bracelet includes a brushed/polished finish for a sturdy, stylish look.