A rocker switch is a type of switch that moves back and forth like a seesaw. It is commonly used to turn devices on or off by flipping the switch up or down. Full definition
The slim volume rocker switch on the right edge is coloured to match the frame, and joined by a round «convenience» key. (pocket-lint.com)
Instead you'll find the power / lock key and the volume rocker switch on the right hand side of the slate (when held in portrait). (techradar.com)
The infotainment system is improved by the use of rocker switches on the console beneath it, making accessing different functions easy. (nextgreencar.com)