Do Not Touch - With Promaster
It is amazing the number of times the simple cable release is needed in photography - particularly now that most cameras do not take a mechanical cable release.
Apart from my Fuji, and your Leica, and a few others I cannot remember, most other serious cameras need an electric command to fire off. You plug something into a socket on the camera and then press a button on the other end of either a cable or a wireless link.
Here is a variety of their releases in their packaging. Note that they are also at a very competitive price. We like having such a large stock for different users.
Studio photographers: note the discrete use of invisible props for presenting the product to the camera. This is the sort of attention to detail that defines professionalism. Amateurs use soup cans...