The RONI (pat-pending) provides you a better grip stability & platform to many accessories. Now you can use your pistol for a greater range faster aiming better accuracy. No pistol disassembly required -just drop it into the shell. Pistol for this Roni must have the below barrel rail to fit it properly. 24cm upper flattop rail - allows combinations of sight magnifier or night vision. Two 2 Picatinny side rails and one Picatinny bottom rail for additional accessories. Optional to add flip-up Backup sights (#FRS / #FFS). Accepts silencers - up to 35.5mm diameter. Optional to add quick release brass-catcher. Including Detachable folding forearm grip rear spare magazine holder & a safety-catch for the trigger's guard. The Roni-G2 fits several types of Glocks (17 18 19 22 23 31 32). Only compatible with Generation 3 and Generation 4 Glocks-specifically those that have a factory Glock laser light rail with a single cross lug. Eligibility: Glocks 9mm & .40 cal - Materials: Aluminum + Polymer - Measurements: - Weight(lb): 3.09 - Length(in): 18.5-22 - Total Rails: 4