Helps you train without going to the range or burning up ammo. Simply insert the laser training cartridge unit into the chamber like an ordinary cartridge. When you pull the trigger, the firing pin activates a switch that turns on the bright red laser dot to indicate the "bullet" impact point. Activates for 100 milliseconds each time the firing pin strikes. Use it to "call the shots" on any standard target or, for a more interactive experience, with the Training Target sold below. Rimless housing prevents the LTS from being extracted and ejected when you rack the slide-perfect for tap/rack/bang malfunction drills. Soft brass housing is fitted with two rubber Mfg: Laserlyte Brass, natural finish, rubber O-rings. Red laser dot. Runs on three Type 377 button-cell batteries, included, good for approximately 3,000 shots. Instructions included.