The wireless SRM mouse is for right-handed use and is suitable for someone with a small hand. The Evolution SRM mouse has an optical sensor and has 4 buttons, including scroll wheel.
The Evoluent C wireless is the streamlined version of the Evoluent-series and has a modern design. This is the wireless version. Because of the handshake position of this vertical mouse, the wrist bends less aside and the forearm less to the inside, and therefore, the joints, muscles and tendons have a way more natural position.