DoubleTapp pad for standard M4 stocks. Provides a positive, non-slip cheek weld for better accuracy and precIsion when shooting. Will not interfere with the actions of the charging handle at ALL positions of the stock, even when fully collapsed or any features of the stock. Custom fitted and digitally cut to match the design of the original stock. (Features our Unique, Double Patent Pending Design called "Charging Handle Cut or CHC")