Abstract: A releasable linking unit has first and second support elements designed to be applied one against the other, said first support element having a catch loop; a hook joined to said second support element and displaceable relative to this second support element; control members having elements for guiding the hook between a locked position and an unlocked position. The guide elements are designed to bias the two support elements one against the other when the hook is fully displaced from its intermediate position into its locked position.