The BAD-T4 is a five (5) function, double-ended wrench. On one end, it is a Gas Cylinder Lock Wrench for the M14 / M1A Rifles and on the other end, it is a wrench for the SEI Gas Lock Front Sight. 100% made in the U.S.A., out of high quality 3/8" thick aircraft grade 7075-T6 aluminum and hard coat anodized in Black, it is a must have for the old school and modern M14 / M1A shooter and enthusiast.