Abstract: Two mating L-shaped steel sheet casing members in one embodiment for sliding doors are secured to a corresponding door and have overlying front walls in the closed state. Each member has a plurality of corresponding locking keeper elements. In the closed state the keeper elements are in interdigitated juxtaposed and preferably welded to the casing members via through optional bores in the casing members, or extend through the side walls of the casing formed by side wall sections. The keeper elements in one subassembly are slotted to allow for misalignment with the other keeper elements for receiving a locking bolt seal shaft. The keeper elements optionally have tongue projections for engaging a gap between the closed doors. An angle iron member shields the rear of the chamber below the lowermost locking element to protect the seal locking body. Other embodiments are disclosed and include cast assemblies with no weldments and a single casing and hasp for use with swinging doors or a rail car plug door.