This steel stand was custom made to support big air mover fans of 60 to 90 horsepower that could be moved in and out of place on angle iron rails. There is some cosmetic surface rust from being outside but they ares structurally sound. It rolls on steel wheels that are 6" diameter and 2.5" wide with a v-groove in the middle that rides on an angle iron rail. We did not get any of the rail. There are 3 of these at the start of this sale but this listing is ONLY FOR ONE UNIT. There are spring vibration isolators on each corner.