1000 lumens output Uses one 18650 battery Magnetic controlled tail switch offers high water resistance and easy operation underwater Standardly included wrist strap fastens the flashlight to the back of your hand Water pressure resistant construction, depth rated to 150 meters High efficiency constant current circuit, constant brightness Reverse polarity protection to protect from improper battery installation Over-discharge protection function Alloy aluminum reflector with professional optical analysis WARNING: The user must have appropriate understanding of lithium ion batteries before purchase. Use caution when working with and using lithium ion batteries as they are very sensitive to charging characteristics and may explode, burn, or cause a fire if misused or mishandled. MISUSING OR MISHANDLING LITHIUM ION BATTERIES CAN POSE A SERIOUS RISK OF PERSONAL INJURY, PROPERTY DAMAGE, OR DEATH BATTERIES MAY EXPLODE, BURN, OR CAUSE A FIRE IF MISUSED OR MISHANDLED DO NOT STORE LOOSE BATTERY IN A POCKET, PURSE ETC. - ALWAYS USE A PROTECTIVE CASE OR BOX KEEP AWAY from metal objects to prevent short circuiting DO NOT short circuit DO NOT use if wrapper or insulator is damaged or torn DO NOT use if damaged in any way DO NOT overcharge or over-discharge DO NOT modify, disassemble, puncture, cut, crush, or incinerate