Swivel fittings connect tubing to a threaded hole. The barb (and tubing) can be freely rotated from the base. A captured O-ring provides a high quality seal against the mating part. Barbed connections are a clean, time tested and cost efficient method of connection. The hoop strength of the tube holds around the barbed fitting. Air Logic's first barb is free of a parting line to create a good seal, additional barbs increase holding force for tube retention.