* Material : Aluminum.* ON-off mode : Touching switch.* Battery : 18650 or 16340 rechargeable battery. (Do not include)* Laser Wavelength : around 650nm.* Working voltage : DC 3.7V.* Total weight : 260g.Battery Installation:* 1.Unscrewing the back cover.* 2.Put the battery in according to the images illustrate below.* 3.Inserting the key， push deeper and rotate it， red spot means off， green spot means on.Operation instructions:* Install the battery， press and hold the switch， the adjustable focus green laser flashlight will begin to work. It will be turned off after release.Package included:1 x Adjustable focus green laser flashlight2 x Key.