Heavy duty steel construction. Each jack includes a large 5" by 8" rectangular steel base plate and frame mounting plate that is supported by its own channel. All scissor arms engage with a tooth gear design to ensure straight line vertical extension and retraction. The 24003D model has a 30" extension with a 5,000 lb. weight capacity. Set of 2 with #20037 crank handle with swivel head. Made in U.S.A.
