Glock Gen 4-5 Grip Frame Slug Plug Al6 No Backstrap Silver NDZ - Choose Your Design NDZ A6 Silver Billet Aluminum Grip Plug for GLOCK 17 18 19 22 23 24 25 31 32 34 35 37 - GEN4 ONLY - use WITHOUT backstrap installed 1000+ High Resolution Permanent Laser engraved images, will not rub off, not painted, custom engraving too - by NDZ Performance Fits flush, prevents snagging, debris from entering or reaching trigger assembly and firing pin Quick install and easy removal, uses spring plunger assembly for retention 100% Aluminum - NOT plastic. Also helps guide mag. into magazine well