MWS Crown Nut ToolRESTOCK DUE EARLY FEB The Bavtac CNT. Yeah, read that again I bet you read it wrong Silly goose! Specifically designed for the MWS platform, this perfectly fits the Crown nuts on the buffer tube. And on the CQBR and Carbine models, the Barrel nut. Made from 4mm steel this tool is durable and will allow plenty of torque transfer to the nut. With 3 8 drive cut outs you can even use this in conjunction with a 3 8 ratchet for extra torque helping to crack