The LG-660 laser sight is an engineering marvel for Smith & Wesson M&P Full-Size pistols. Interchangeable between calibers, the LG-660 Lasergrips directly mimic the look and feel of the original grip, with the tactical impact of laser sighting. Activation is in the rear of the weapon on this model, instinctively springing to life when the pistol is held in a natural firing grip..