The Workrite 3170-17TGB keyboard arms offer unprecedented smoothness and adjustability for maximum comfort and have a sleek low-profile progressive ball bearing slide track for smooth, consistent operation. The low profile design of the Workrite 3170-17TGB maximizes knee clearance, with independent height and angle controls. The Workrite 3170-17TGB features no-knob, no-lever, Lift-N-Lock for one-touch height adjustment, and its low-profile design maximizes knee clearance