Regulator, 15 psi, 1/8 in FNPT, Exchange, Used on all ABI Synthesizers. Regulator only. No fittings or Gauge. Since this is an exchange item, you must return your old item complete with all components. If you do not return your item or you return it missing components, you will be charged as though you purchased a new item without exchange. If you do not want to send your old item back to us, you should purchase this same item as non exchange from us.