HDE Mini Portable Black Light 395 nm UV Ultra Violet Stain + Counterfeit Detection Flashlight Small lightweight and compact design makes easy to travel or carry anywhere Perfect inspection tool for cleanliness of hotel rooms, counterfeit bills, scorpion spotting, and bed bugs Can detect items the naked human eye can't; LED bulbs are energy efficient to conserve battery life Built in LED flashlight provides additional seeing options in the dark Size: 3.5" ; Power Source: 4X AA Batteries (Not Included)