The CAST S.p.A. fitting according to the norms ISO 8434-2/ SAE J514, is a mechanical fitting traditionally used for high pressure oleo-dynamic systems. The sealing is made by the contact between two metal surfaces, with no deformation of the single components. The coupling between the body of the fitting and the flared tube (cone angle 74°) is guaranteed by the tightening nut and by the pressure sleeve on the inside. This allow to realize a fast assembling-disassembling tube making the easiest realization of complex oleo-dynamic systems.