The DS-124 Defender Series Accu-Grips Laser Sight by Crimson Trace fits Smith & Wesson J-Frame (Round Butt) and Taurus Small Frame Revolvers. The Defender Series sets a new standard in laser sighting systems by providing cutting edge design, superior technology, and an affordable price tag. The DS-124 features Beam Lock Adjustments so that the user can easily adjust laser sighting for both windage and elevation, and the unit is pre-sighted at the factory at 50 ft. The Top N-Gage Activation Button provide a large, easy-to-find, bright red activation button, which emits a powerful (5mW peak, 620-670nm, Class 3R) red aiming laser. Fits Smith & Wesson Airlight, Airweight, Bodyguard (Except Polymer-Framed Models) Chief’s 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. Round Butt Only. Fits Taurus Small Frame Revolvers (85*, 94, 605, 650, 651, 731, 850, 851, 856, 905, 941) Does not fit Taurus Small Frame Revolvers with Polymer Frame. *Does not fit Taurus 85 Models manufactured after 2014.