Releasable fastening of a first part to a second part incorporated in an aircraft

Aircraft internal trim (12) plastic fastening (18) has one end (24) in the trim and the other held in the C profile mounting rail (64) by an attachment (38) against the support (78) with clip (42) and sprung lock (46) in a frame (44) and is detached by pressing a release tab (56) with a tool.