Seiko NH35 Automatic Movement: Built by the world renowned Seiko Group, our NH35 Automatic Movement is a reliable and accurate time keeping choice. The NH35 is both hacking and self-winding with a power reserve of 41 hours. For full power reserve Seiko suggests winding the crown 55 times. The NH35 has 24 jewels and a -20 seconds to +40 seconds per day accuracy. CASE MEASUREMENTS Diameter 39mm, thickness 13.8mm, lug to lug 45mm, lug width 20mm. CASE EXECUTION Sandblasted stainless steel case with IP stealth black plating, laser engraved caseback ring and firefighter helmet caseback with coloured glass visor. Note: As our casebacks are screwdown the position of the firefighter helmet visor design will not be the correct way around. The helmet will be in the position that the caseback teeth finish on.  GLASS Flush glass finished with a medium blue tint and anti-reflective coating. DIAL Textured charcoal dial with rose gold applied indices filled with green Super-LumiNova, 3pm date window, polished hands filled with blue Super-LumiNova and fire bell chime inspired seconds hand. CROWN Sandblast IP stealth black crown with a brass inset made from a 100 year old British brass firefighter's helmet. STRAPS All straps have a 20mm lug distance and a quick release functionality allowing you to change straps without any tools required. WATER RESISTANT 100 Metres / 10ATM.