1 Each. Sit-to-Stand Three-Leg Base is part of Lorell Quadro Electric Adjustable-Height Workstations that accommodate different users. Once paired with a knife-edge tabletop, the complete workstation lets you alternate between sitting and standing. Flexible design supports an L-shape desk with height-adjustable function for an optimum work environment. Dual motor allows synchronized and precise compensation for uneven loads. With smooth quiet movement, the Flex Frame base adjusts from 24" to 50" for 48" to 72" wide tabletops at a speed 1.3" per second. Base features built-in temperature and overload sensors as well as ISP (intelligent system protection) anti-collision safety feature.