Sekonic Light Meter: Calculates your f-stop, shutter speed, ASA and DIN indexes ASA scale: 6 - 12,000 DIN scale: f/1 - f/64 Shutter speed scale: 1 sec - 1/2,000 sec. Works up to approximate depths of 60m. / 200 ft. Accurate up to ±0.5 EV Powered by a 1.3V Mercury battery Excellent condition, still in the box Manual included Call Today - 1-877-SCUBADV (1-877-728-2238)