pin clearance opening 54 in the center of the lock bar 40 may have a bevel or chamfer 72 to fit more closely with the inner radius of the bend or junction between the two legs 36 and 38 of the lance tab 34 as the junction of the outward extending leg 36 and parallel leg 38 of the lance tab 34 acts as a fulcrum or pivot point for the lock bar 40 it will be seen that the distal lock tab end portion 44 of the lock bar 40 is urged toward the front face 50 of the connector 24 thereby also urging the lock tab 56 into the aligned lock tab passage 32 and upper portion 16 of a connector pin passage 14 thus once the lock bar 40 is installed with its spring 64 the lock tab 56 automatically engages the connector 24 and underlying upright 12 to prevent the connector 24 from lifting relative to the upright 12 thereby assuring that the shelving assembly 10 cannot be disassembled either intentionally or inadvertently without positively and intentionally pivoting the lock bar 40 outwardly away from the front face 50 of the connector 24 against the pressure of the spring 64 yet the lock bar 40 is easily released by intentionally pulling or prying outwardly upon the.