21 LED Emits 395nm UV (Ultra Violet) wavelength. Suitable to look for cats, dogs and other animal's urine on cloths, carpet, rugs, etc. Made of sturdy and durable aluminum alloy material, no functional problems under 4.92ft/1.5m drop test. Essential tool for pet lovers, portable and lightweight torch, convenient to carry to anywhere. Powered by 3 x AAA batteries, included in the package.