the sb 1000 had a welded sheet metal body with either a drawn or welded steel nose piece. the nose piece was threaded and was streamlined to reduce drag while the bomb was attached to the aircraft. the sb 1000 had no base plate and was filled through the nose with a central exploder tube which ran through the center of the bomb from the fuze pocket to the nose. the tail of the sb 1000 was constructed of drawn steel and had four fins inside a circular strut. the sb 1000 was suspended horizontally by an h-type lug or trunnions if carried by dive bombers. the sb 1000 was filled with a mixture of rdx biscuits within a "trialen 105" matrix. trialen 105 was a mixture of 15% rdx, 70% tnt and 15% aluminum powder. due to its thin case and powerful explosives, the sb 1000 was vulnerable to enemy gunfire.