Swivel out mouse platform Swivel out platform under keyboard when not in use Ultra-thin platform features Optimizer document holder Removable LeatherRite palm support No Knob No lever Lift N Lock One touch height adjustment This keyboard system features our Advantage-Dual platform with two swivel-out mouse surfaces and our Pinnacle 2 Value Arm. Dual mouse platforms enable users to alternate mouse positions, reducing muscle strain. The efficient design of the mouse platforms a factor in repetitive stress injuries.