Super-Strut 3 1/2” 702 Pipe Rigid Steel Conduit Clamp Complete NOS USA 276T.
 
Some of them are just another company or color but all are the same size. New old stock complete with nut and bolt.
 
This Power-Strut or Superstrut clamp is designed for 3 1/2"-inch rigid metal conduits. It's a complete, new old stock item that comes with bracket mounting for easy installation. The compression connection type and steel material ensure durability and long-lasting performance. The clamp is available in many colors and features a unit type of a conduit clamp accessory, which makes it a great addition to any electrical equipment and supplies inventory. The rigid flexibility of the clamp is ideal for industrial and commercial settings. Made in the United States, this is a top-quality product that guarantees quality and safety.