Although there are different ways to design silicone-rubber keypads, most feature a similar format consisting of silicone rubber material around an electronic switch in the center. At the bottom of the silicone rubber material is conductive material, such as carbon or gold. Below this conductive material is a pocket of air or inert gas, followed by the switch contact. So, when you press down on the switch, the silicone rubber material deforms, thereby causing the conductive material to make direct contact with the switch contact.

Silicone-rubber keypads also use the compression molding properties of this soft and sponge-like material to produce tactile feedback. When you press down on the key and release your finger, the key will “pop” back up. This effect creates a light tactile sensation, thereby telling the user that his or her command was properly registered.