The Nikon AR2 release has the female thread that fits male Leica-threaded release posts of F, F2, Nikkormat, and EL2, and (I think) the FM and FE cameras, and older Leica cameras.
The Herco-Minette release has a soft release (as shown in the photo on the end near the tip) that can be separated from the cable and used by itself. Its held to the cable end by a spring & ball retainer inside the soft release. The retainer ball fits into a groove machined into the end of the release.
To remove the soft release you simply grasp it with one hand and the cable end in the other and pull it smartly away from the cable end. The Herco-Minette release cannot be used without the soft release piece as shown on the end of the cable. Otherwise the tip of the cable sticks out too far from the housing.
Both of these are nicely made.