As pictured 4 CGA-540 Brass Fittings and HP hoses to hook up to 4 tanks. $40 or trade for whatever make an offer. PM.or Post if interested. CGA-540 is the standard fitting for the attachment of a compressed gas cylinder to the required regulator or transfer. All hookup fittings are 1/4 in NPT. They are extras from my nitrox mixing station.