One side of external thread flat 0.208 in. Nom; underside of hex head has an o-ring groove 0.010 in. Nom wide by 0.046 in. Min 0.052 in. Max deep with 1.475 in. Min 1.481 in. Max od and 1.301 in. Min 1.311 in. Max id; body undercut below head 0.140 in. Nom wide by 1.160 in. Nom dia; o-ring groove finish 32.0 microinches max; underside of head chamfered 10.0 deg min by 20.0 deg max; threads conform to mil spec mil-s-7742