Replacement light head/battery holder insert for LOLA backup light.
The ultimate in underwater illumination technology. Four LEDs are enclosed in a waterproof/environmentally sealed stainless steel housing three inches long and one inch in diameter. It weighs only 3.5oz (125g), ~1oz in water, so it can be comfortably mounted on a mask strap for hands free operation. Simple twist of rear bezel activates the light using a magnetic reed switch.
Puts out enough light for survey work, camera operation, or to safely guide you out of the cave in the case of primary light failure.
Three AAA batteries will power this baby for days. Virtually indestructible.