The Thorlabs L490 Lab Jack is their largest, with both the top and bottom plates measuring 4 inches X 7 inches. Both plates have 19 holes drilled and tapped to 1/4-20. Able to support over 75 pounds, and will raise from 2.2 inches up to a fully extended height of 4.4 inches. This Lab Jack is made primarily of black anodized aluminum, with stainless steel axles and lead screw. This jack utilizes a dual-pantograph design to ensure parallel movement and rigidity.