PLC19BK BLACK color plug-lock inserts prevent accidental disconnection of C20 plug-in power cords from C19 output receptacles. IEC 60320 plug-in electrical cords are frequently loose-fitting and are often subject to accidental disconnection during routine network maintenance. To prevent critical equipment plugs from getting knocked loose, place a plug-lock insert over any C20 input cord and connect it to any C19 outlet. The insert strengthens the connection of the plug to the outlet, keeping critical equipment plugged in and running during routine rack access and maintenance. Plug-lock inserts provide a no-clutter alternative to common zip-tie cord retention schemes and a low-cost answer to expensive proprietary locking plug and outlet hardware. PLC19BK plug-lock inserts ship in packages of 100.