Prime-Line 3/8 in. Galvanized Cable Clamp (2-pack) GD 12253 - The Home Depot
The Plumber's Choice 3/4 in. Steel Cable Clamp; Hangs Tubing, Wiring, Ropes, for PEX, Plumbing, Marine, Automobile; Galvanized 34CPSWG - The Home Depot
National Hardware N100-261- 1/4-in Wire Cable Clamp in Zinc Plated in the Chain Accessories department at Lowes.com