Airmont Products AP-10921, Heavy Duty Adjustable Porcelain Wire Holder, Reinforced Steel Saddle, Adjustable Steel Clamp Fits Around Any Pipe or Pole, Ceramic Head for Cables or Wires as an Insulator - Amazon.com
Steel Zinc Plated Pipe Saddle Clamp - Thick HEAVY DUTY 22mm to 165mm diff qtys | eBay