COUPLER PLUG: The air hose fittings include 2 3/8 body air couplers with 3/8in NPT thread and 2 3/8 body air plugs with 3/8in NPT thread. Item Type: Air Coupler Plug Kit. 4 x Air Coupler Plug Kit. SIX LOCKING BALLS: There are six locking balls in the connector to securely secure the plug.
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