The NcSTAR Compact Red Laser Sight with Weaver Mount is a red laser with a frequency of 635-655nm and is a Class IIIA laser. The maximum output is less than 5mw. The weaver mount will easily clamp onto compact and subcompact pistols that have a weaver style accessory rail. This laser sight is fully adjustable for windage and elevation and has a side to side toggle on/off end cap switch. It features an all aluminum construction with a black anaodized finish. The laser sight uses 2 AG13 button cell batteries (included) and inlcudes the mounting hardware. Red laser: Freq. 635-655nm, Class IIIA laser Maximum output: less than 5mw Weaver mount will easily clamp onto compact and subcompact pistols that have a weaver style accessory rail On/Off Rear Cap Switch is Easily turned On or Off with your Trigger Finger All aluminum construction with black anaodized finish Uses 2 AG13 button cell batteries (included) Includes mounting hardware