BSU-33 Fins are general purpose fin assemblies for 500 lb. general purpose bombs. They are the smaller "cousin" of the MK-84 conical fin. Delfasco specializes in the stamping, machining and finishing of these fin assemblies. The BSU-33 and subassemblies are fabricated from steel, cut, formed, machined, assembled and welded to Military Specifications and drawing requirements.