5steel alloy, 4140h or 8640h, spec qq-s-624; 51.062 in. O/a lg; 2.375 in. Id; 3.370 in. Od; thd on both ends; first end 3.375-12-un-3a externally thd; 1.438 in. Lg of thd; second end thd identical with first end; w/two mtg brackets bolted through tube