LG-639G Green Lasergrips are a rear-activated green laser sight is compatible with GLOCK Compact pistols. Lasergrips fit Glock Gen 1 & 2 19- Gen 3 19/23/25/32/38- Gen 4 19/23/32 Gen 5- 19. Will not fit 19X. Featuring Crimson Trace’s famed Instinctive Activation, which allows the laser to be activated with a normal firing grip, the LG-639G includes a Master On/Off Switch for completely powering down the unit. User-installed in moments by attaching securely to the gun frame, this laser sight is fully adjustable for windage and elevation. Provides 2 hours of run time with (4) included 2016 Lithium Batteries.