Crimson Trace LG-660 Smith & Wesson M&P Full-Size Red Lasergrips - Black - 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. The LG-660 received the Academy of Excellence Award for "High Tech Product of the Year" in 2008. Activation Location: Rear Activation Activation Type: Instinctive Activation Attachment: Grip Attachment Beam Intensity: 5MW Peak, 633NM, Class 3R Red Laser Dot Size: Approx. 0.50in At 50ft Smith & Wesson M&P Full-Size: Fits Smith & Wesson M&P Full-Size .9mm, .357 Sig, .40 S&W, .45 Acp Except Ambidextrous Safety Models. Does Not Fit M&P M2.0 Models