Seiko Navigator Timer 'Proof'

While we love the romance of chronographs, moonphases, and minute repeaters, it’s one of watchmaking’s simplest complications that proves the most useful in everyday life: the GMT. A GMT watch tracks a second time zone at a glance. Whether you’re a pilot, a jet-setter, an international playboy (we don’t judge), or simply coordinating calls across continents, the GMT remains one of the most practical tools ever fitted to a wrist. As frequent travelers, you’ll often find a GMT strapped to our wrists. And if you were to poll our colleagues in the watch industry, you might be surprised by how many would agree. For the global age, these are arguably the most functional watches in the game — and they usually deliver some of the coolest designs to match. One of our all-time favorites is the Seiko Reference 6117-6410. Produced in the late 1960s and early 1970s, it features a distinctive case design, a rugged in-house movement, and a striking dial-and-bezel layout, all at a price that still feels like a steal. This early example becomes even more desirable thanks to its “WATER PROOF” stamped dial — a short-lived detail replaced later by “WATER RESIST.” The Reference 6117-6410 features a 38.5mm stainless steel tonneau case with a domed acrylic crystal and an unsigned 4 o’clock crown. Its black dial is wonderfully legible, with a luminous minute track, applied indices, a crisp red/blue day-night scale, a red GMT hand, and a date at 3 o’clock. Paired with Seiko’s automatic Calibre 6117A and an excellent multi-link bracelet, it makes tracking a second time zone effortless. Robust, handsome, and endlessly practical, the 6117 is the kind of vintage GMT no serious collector should pass up — especially one this well-preserved.