Replacement Rubbers for Test Plugs – Osborne No. 439 Replacements Rubber for the Wing Nut Test Plugs are also sold individually. Specify preference....Read More
Test Plugs – Osborne No. 438 Osborne Wing Nut Test plugs are made of cast iron malleable, they can handle up to 40 P.S.I. of air, and temperatures up to 225 degrees Fahrenheit. Designed and deve...Read More
