The Photon Micro-Light II has a bright red LED that boasts a high output of 4.5 lumens in a super-compact size. Squeeze the button for momentary on or use the sliding on/off switch. The Photon Micro Light II is built incredibly strong for years of use. The lithium batteries are replaceable and offer a long shelf life too. Great for use on keychains or clip to gear with quick-release ring.