Bomb resembles the SD 1 H.E. bomb and is of approximately the same weight and size.
Body is constructed of concrete reinforced with irregularly shapped metal chippings.
A normal eight-vane type of tail unit is secured to the body by a bolt embedded in the concrete cast. Lengths of iron wire soldered to the tail securing bolt and to the metal tubing in the nose of the bomb serve to strengthen the cast concrete. The specimen examined was unpainted and devoid of markings.