Purchased two for the cleaning wheels I bought and they work great. Ended up using one to hold my wire wheel on.
Spacers work great at getting the polishing pads out away from the machine to allow you to get into tight corners. Fast shipping and good tracking updates on the order.
The fine wheels I purchased bring aluminum up to a pretty good shine with out the use of compounds. Works great if that`s the finish you are looking for. If you want more of a satin finish try the rough cleaning wheels. Shipping was fast and the products are good value for the price. Thumbs up from me!