the wholes were a little off set from the original but not so much that you could not install the screws. the base is sturdy and the shock feels good. the lever to control the base rocking back and forth and the height adjustment is really close to the base of the chair, but you can use it. I painted the base (from black) off white with a made for plastic paint, they look really good and the paint absorbed well. Im buying 3 more sets for all the rest of the chairs that I need to replace. the 4 stars and not 5 is only because of the lever being too close to the bottom of the chair. You might not even have this problem, but I do and I'm pointing it out.