LG-207 laser sights for Smith & Wesson K, L & N-Frame revolvers feature a hard polymer material that provides ideal grip security for large caliber revolvers. The laser activation switch is located in front, making activation "instinctive" when you assume a normal firing grip on the revolver. Lasergrips fit: Both Round and Square Butt Smith & Wesson Models 10 Through 29,48,53,56,57,58,64 Through 68,242,329,396,530,547,581,586,610,617,624,625,627,629,648,657,686 and 686. Does not fit K-Frame Scandium Revolvers. Does not fit with target hammer.