Threaded component of a quick release coupling whose function is to allow connection of the coupling to hydraulic system. Adapters are characterised by different threads and shapes internationally standardised. (for instance DIN 24°, JIC 37°, ORB, ORFS, ...)

Chemical-thermal treatment whose aim is to give a great surface hardness of a component made in steel. This is obtained thanks to the enrichment of surface layer with Carbon and Nitrogen.