Inspired by two milestones in Seiko’s diving heritage, the SJE099J1 features an ice-blue “clearwater” design that draws on the brand’s first Japanese Diver’s watch from 1965 and the professional Seiko Marinemaster of the 2000s. The original 1965 Diver marked the beginning of Seiko’s enduring commitment to robust dive watches and proved its reliability on extreme expeditions to Antarctica, the North and South Poles and Mount Everest. The Marinemaster further cemented this legacy, created specifically for professional divers with a strong, durable construction.
This modern Marinemaster interpretation carries forward signature elements from the 1965 original, including its distinctive silhouette and bold hour markers. The horizontal line patterned dial delivers a refined marine-sports aesthetic, while the mirrored-finish lugs enhance light reflection. Thick Lumibrite-coated hour markers provide excellent legibility, and a sapphire exhibition case back — a first for a Seiko Diver — allows a view of the movement within. Despite the box sapphire crystal and display back, this is the slimmest Seiko mechanical diver at just 12.3mm.
Powering the SJE099J1 is the new slim in-house calibre 6L37, offering strong accuracy of -10 to +15 seconds per day and a 45-hour power reserve. Built to meet Seiko’s strict ISO Diving standards, this model reflects the Prospex philosophy of “Professional Specifications” — timepieces engineered to be practical, reliable and durable in extreme or everyday environments for sports lovers and adventure seekers alike.
