Morris Products 90631 Ground Pipe Clamp, For Rebar and Direct Burial, 1/2 - 1" Water Pipe Range, 2 -10 Wire Range, 1/4 - 20 Screw Thread Direct Burial Ground Pipe Clamps for Pipe and Rebar - Direct Burial Rebar Pipe Clamps for grounding to Water Pipe and Rebar Direct Burial Rated Ground Pipe Clamps are cast of high strength, high conductivity Copper alloy For Connecting Grounding Conductors to Water Pipe, Copper Tubing, Ground Rod or Rebar UL Direct Burial Ground Pipe and Rebar Clamps have screws made of Copper UL 467 listed for direct burial in earth or concrete