Abstract: A shear connector includes a plug connector having front and rear insert portions on opposite sides of the shear plane that are held together by a shear bolt scored to shear at a predetermined force, and which is threaded directly into openings in the rear insert in such a way as to eliminate relative movement between the shear bolts and the rear insert during shearing. Pin contact sections extending rearwardly from the front insert are scored at the shear plane to shear at a predetermined force. By varying clearances between the pin contact sections and the sides of the openings of the rear insert into which the pin contact sections extend, groups of contacts can be made to shear at different times, thereby reducing the force required to shear each group without unduly weakening the contacts.

Abstract: A pair of mateable units with polarizing means for controlling mateability of the units comprising a member rotatably mounted on each of the units one of the members having an extension of predetermined shape and the other member having a recess of predetermined complementary shape for receiving the extension on the one member. The members each have a slot in one end for receiving a screw driver to rotate the members to adjusted position without removing, resetting and reassembling small components.