Moroso 63731 Moroso Radiator Hose Bleed/Drain - 3/8in Petcock - 1-1/2in to 1-1/2in Hose - Cast AluminumMoroso 63731 Moroso Radiator Hose Bleed Drain 3 8in Petcock 1 1 2in to 1 1 2in Hose Cast Aluminum Radiator Hose Bleed or Drain Are spliced into the upper radiator hose to add a bleed or spliced into the lower radiator hose to add a drain Cast aluminum with a 3 8" brass petcock