These clamps are used in CATV, telephone, LAN, and other utility installations to support and secure cable, wire, conduit and pipe. All clamps are made of high quality steel and are galvanized to resist corrosion. One hole clamps are available in a full range of sizes to accommodate 3/16" to 1-1/4" cable. Two hole clamps are available in a full range of sizes to accommodate 7/16" to 3-1/2" cable, R.E.A. accepted. Manufactured in the USA.