Tritium gets most of the attention in military watches, but the Marathon OSAR-D shows how well a light-charged lume can work. Reference WW194006SS-2001-KIT is the 41mm Original Search and Rescue with Date in brushed stainless steel, with a black Type I dial and a stainless steel bracelet, lit entirely by Marathon's MaraGlo.

MaraGlo is a photoluminescent compound: expose it to light and it glows for several hours. Marathon applies it generously to the OSAR-D's oversized geometric indices, to both main hands and to the bezel pip, so after a day outdoors or a few minutes under a lamp the whole dial lights up. Because the indices are large and geometric, orientation is quick even before your eyes fully adjust to the dark.

The rest of the watch is pure SAR. The 41mm case is 13.5mm thick, rated to 300 meters and protected by a screw-down crown with guards. The date at 3 o'clock is magnified 1.5x by a cyclops on the sapphire crystal, a signature of the original SAR-D issued to Canadian SAR Techs in the early 2000s. A Swiss Sellita SW200-1 automatic keeps it running.

OSAR-D Specifications: WW194006SS-2001-KIT

• Ref. WW194006SS-2001-KIT
• 41mm 316L stainless steel case, 13.5mm thick, 48mm lug-to-lug
• Swiss automatic Sellita SW200-1, Incabloc, 26 jewels
• 30 ATM water resistance, screw-down crown and guards
• Sapphire crystal; date at 3 with 1.5x cyclops
• Black Type I dial with MaraGlo geometric indices and hands
• 120-click unidirectional bezel, MaraGlo pip
• Stainless steel bracelet, 20mm lugs

Charge it in the sun and let it shine after dark.