This is a new 7/8" straight thread x 1/2" compression check valve for older Campbell Hausfeld, Speedaire or Sears air compressors. This is a special check valve made for these compressors it has a 7/8" male straight thread that screws into the tank with a high temperature gasket seal. Some of the original valves that this is designed to replace were made of aluminum and some were brass; this will replace either one. *Note this will not work on all Speedaire, Campbell, and Sears compressors most of them have regular pipe thread check valves.*.
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