#1 Rate Stain UV Detector ,Alenca 51 UV LED 395 nm Ultraviolet LED Flashlight Blacklight Perfect Urine & Stain Detector Torch Spot Scorpions,Clear Ultraviolet Ray,3 AA Batteries 51 UV LED bulbs allow to cover a larger area Hotel room inspection, rodent contamination Essential tool for law enforcement, postal inspections, customs, medical forensics, HVAC repair Emits 395 nanometer wavelength, hunting scorpions,discovering urine &stain Uses 3 AA Standard Alkaline Battery ,which cost same price as AAA, but last 3 times longer than AAA