Height is adjustable on this round rack every 3" from 48" to 66". Uprights are made of 1" square tubing. Ring is 36" diameter. Adjustable levelers and rubber-tipped shelf supports are included. Can be used with our 2" (240290) casters. Bolted construction. This rack does not rotate. Folds for easy shipping and storage. Because of the load on this rack, casters are not recommended with this product.