The propane gas line system only accepts one regulator. Item: 1lb Propane Regulator to 3/8" Male Flare Adapter. 1Pc x 1lb Propane Regulator to 3/8" Male Flare Adapter. Connection: 1" x 20 Female Throwaway Cylinder Thread to 3/8" female flare (5/8"-18UNF) Thread.
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