The LG-305 LaserGrips provide a more substantial grip handle than our deep-concealment LG-405 model, both covering the prolific Smith & Wesson line of J-Frame Revolvers (Round Butt).(Grips/Laser only, gun not included.)Specifications: Activation: Instinctive Activation; Front Material: Rubber Overmold User Adjustable: Both Windage and Elevation Master On/Off Switch: Yes Warranty: 3 Years Complete Beam Intensity: 5mw peak, 633nm, class IIIa laser. Maximum output that federal law and technology allow. Dot Size Approximately: 0.5" diameter at 50 feet. Power Source: Two #2032 lithium batteries (included); over four hours of on-time use and a five year shelf life Fits: Smith & Wesson J-Frame... Airlite, Airweight, Bodyguard, Chiefs Special, Centennial, Ladysmith, models 36, 37, 38, 49, 60, 63, 317, 331, 332, 337, 340, 342, 351, 360, 442, 637, 638, 640, 642, 649, 651 and 940 with round-butt J-Frame.J Round Butt Overmold, Front Activation, Full Grip