Monitor arm provides 7-1/2 in. of height adjustability and extends 19-1/2 in. from the base. Swivels 180° and tilts forward and back 80°. Clamp mount system for desks up to 4-1/4 in. thick and grommet mount hardware fits desks up to 2-1/4 in. thick. For LCD monitors up to 30 lb. 5-year warranty. Sold by each.