Needing to secure your collapsible stock for a featureless AR build? Aim Sports has you covered. These pins are designed to work with either Mil-Spec or commercial buffer tubes and available for the Mil-Spec M4, Magpul, or Daniel Defense stocks. They also fit stocks with similar locking systems. With easy installation and an unbeatable price, why purchase a new fixed stock when you can convert your existing collapsible stock in seconds.M4 style pin is compatible with USGI M4, B5, LMT SOPMOD, VLTOR, BCM, Blackhawk!, and LWRC Stocks.Magpul style pin is compatible with Magpul MOE,CTR,SL,ACS,STR Series Stocks.This product has not been approved for legal compliance by any state or local firearms regulatory authority. Please consult with a competent firearms attorney before attempting to make your rifle compliant with state or local assault weapons ban laws.