Sunpro CP7584 Copper Tubing Kit Can be used on boost and vacuum gauges 72"l x 1/8"w copper tubing with 1/8" and 1/4" national pipe thread engine fittings and a 1/8" gauge fitting Designed for mechanical pressure or mechanical boost gauges T-connector is recommended for boost and vacuum applications Should not be used for fuel pressure gauges or with barbed fittings