Diving in style: At 40 millimeters in diameter, this Ahoi is very large, and very blue too: siren blue. It also tells time in the dark, and the day’s date is easily visible even in murky waters, all quite automatically so—as NOMOS caliber DUW 5101 is at work within. Glance through the sapphire crystal glass back and you can watch it as it divides time. The blue luster comes from the tempered blue balance spring of the NOMOS swing system, the watchmaking company’s proprietary escapement. We think it’s just as beautiful as the blue dial.
Dimensions: diameter 40.3 mm; height 10.64 mm
Case: stainless steel, bipartite; curved sapphire crystal glass; stainless steel back, fixed with six screws
Weight: 70 g
Dial: siren blue, hour indexes with blue superluminova (green luminescence)
Hands: rhodium-plated hour and minute hands and with superluminova inlay in white (green luminescence), seconds hand neon orange
Water resistance: 20 atm (suitable for diving)
Power reserve: up to 43 hours
Strap: textile strap blue-black with winged clasp, size M
Lug width: 20 mm
Includes: leather case; warranty booklet; cleaning cloth and our NOMOS catalogue
NOMOS caliber DUW 5101—ticks automatically and doesn’t mind counting the days. The date ring is set around the movement, keeping it flat and elegant despite the complication—a patent-protected construction. The bidirectional winding rotor is highly praised for its excellent winding performance, and the whole movement for its meticulous rate. A few differences to its predecessor, the NOMOS caliber Zeta, identifiable by the denotation Deutsche Uhrenwerke, DUW for short: The NOMOS swing system is now officially setting the pace—recognizable by the tempered blue balance spring (and of course by the inscription on the three-quarter plate that reads “DUW”). Some of the technical details: decentralized seconds, stop-seconds mechanism, Glashütte three-quarter plate, NOMOS balance bridge, 27 jewels, bidirectional winding rotor, Incabloc shock protection, DUW regulation system, adjusted in six positions, tempered blue screws, rhodium-plated surfaces with Glashütte ribbing and NOMOS perlage.