Choate Tool T.C. Contender M-4 Telescoping StockMulti Calibers. We used a steel adapter housing to allow the M4 stock to be attached to the T/C pistol grip. This stock offers the most versatile length of pull you will find. It will go from youth to adults length of pull with just a pull on the stock All NFA Rules apply. Federal law prohibits use with barrels shorter than 16 inches. Specifications for Choate Tool T.C. Contender M-4 Telescoping Stock: Manufacturer: Choate Tool Gun Model: Thompson Center Contender Heavy Rifle Country of Origin: USA Features of Choate Tool T.C. Contender M-4 Telescoping Stock Telescoping configuaration for adjustable length-of-pull Uses Choate M4 style butt stock includes sealed battery compartments Package Contents: Choate Tool T.C. Contender M-4 Telescoping Stock What firearm models does the manufacturer say Choate Tool T.C. Contender M-4 Telescoping Stock is compatible with? The manufacturer says that Choate Tool T.C. Contender M-4 Telescoping Stock is compatible with Thompson Center Contender Heavy RifleChoate Tool CMT-09-01-24: T.C. Contender M-4 Telescoping StockMulti Calibers