A cap having a stinger adapted to be inserted into a bore of a subsea well element. The stinger includes locking means for locking to a profile in said bore, which locking means include a plurality of locking dogs. The locking dogs exhibit a large inclination face and a small inclination face, and are adapted to be actuated in a radial direction by an actuation sleeve. The small inclination face is divided by a slot, in which slot the large inclination face is arranged. A cam is arranged on the actuation sleeve and is adapted to extend into said slot. Alternatively, the small inclination face is divided by a cam arranged on the locking dog, on which the large inclination face is arranged, which cam is adapted to extend into a slot in the actuation sleeve.