Machined to fit seamlessly while bringing both artistry and rugged engineering to John Browning's classic 1911 design, Master Series Lasergrips are sure to impress. Featuring ergonomic and aggressively durable G10 side panels with a rubber overmolded activation button; these are the ultimate laser sights. It has a master on/off switch and features Instinctive Activation, so that the laser sight automatically springs to life when the weapon is held in a natural firing grip. *Note- fits 1911 and 1991A! full-size frames, including Auto-Ordnance, Les Baer, Colt, Kimber, Nighthawk Custom, Olympic Arms, Para-Ordnance (full-size, single stack), Safari Arms, Sig Sauer, S&W, Springfield Armory, Taurus, Dan Wesson, Wilson and most other 1911's w/grip screws measuring 3 1/16" apart.