This 2 AAA penlight is cULus - 913 listed Intrinsically safe. It is ultra-compact and super slim with a powerful light output designed to illuminate very tight spaces. The tail-cap switch provides momentary or constant-on functionality. Includes the NS-HMC12 mounting clip. The clip can be attached to virtually any hard hat or helmet using a very powerful self-stick PSA adhesive. Power comes from 2 AAA batteries (included).