Rocker switches control circuit on/off or gear switching by rocking the button up and down. Rockers are commonly used as power switches for electronic devices. Their contacts are classified into single-pole single-throw (SPST) and double-pole double-throw (DPDT) types, and some switches also feature indicator lights. Rockers are widely used in household appliances such as water dispensers, treadmills, computer speakers, electric bicycles, motorcycles, plasma televisions, coffee makers, power strips, and massage machines.