The HellermannTyton 561-03301 is a Set of 4.3-5.3 mm Clip On Cable Markers with Wire Labels & Markers that come in various colors and are imprinted with L1, L2, L3, N, and EARTH. This product is designed to aid in the quick and accurate identification of cables, connectors, and wires in a given system. The markers are designed to be quickly attached and released from cables and wires in order to accommodate changing cable configurations. These Clip On Cable Markers are ideal for use in data, electrical, audio/visual, and telecommunications applications.