Standard U-Bolt Standard U-Bolt 304 Stainless Steel Finish Plain Thread Size 1/4 In.-20 Thread Length 2 1/2 in Inside Length 2 15/16 in Inside Width 7/8 in Pipe Size (In.) 1/2 in Characteristics Has Coarse Rolled Threads for Steel or Wrought Iron Pipe Sizes Includes 4 Hex Nuts