This is a Surefire Flashlight, model E2T-MV.
This groundbreaking light is designed for maximum versatility" serving as both an everyday carry light and an improvised weapon light. The Tactician's dual-output LED is paired with a proprietary reflector to create our MaxVision(TM) Beam" a useful wall of light that fills in the space around you. Hand-tighten its front bezel to set the light to deliver all 800 lumens for longer-range or tactical tasks; rotate counterclockwise a quarter-turn for 5 lumens of light for those tasks requiring less light and more runtime. Either setting is activated in momentary-on mode with a press of the tail cap; twist for constant-on mode. A lightweight but durable aerospace-aluminum body is knurled for a secure grip" and a Mil-Spec hard anodized finish protects against abrasion and corrosion. Because you're going to want to take this portable powerhouse with you just about everywhere you go" it features a robust pocket clip for secure bezel-up carry in a pocket" pack" or purse.
Features:
Highly versatile light
Dual-output LED
Either setting is activated in momentary-on mode with a press of the tail cap
twist for constant-on mode