Abstract: A single-sided fitting comprising a shaft with two or more axially extending legs. Each leg has a catch which extends radially outwardly from the leg. A clamping plate has two or more holes each receiving a respective one of the legs. A projection is carried by the clamping plate and extends axially between the legs towards the catches. The clamping plate and projection are axially movable along the shaft to a locking position where the projection is positioned between the catches thus preventing the catches from moving radially inwardly. Means are provided for preventing the clamping plate and projection from withdrawing back along the shaft away from the catches after they have been moved to the locking position. For instance an internally threaded nut may be carried by the shaft, the clamping plate being positioned between the nut and the catches, wherein the nut can be spun along the shaft to engage the clamping plate in its locking position.