The Assault RC Foam Buster Break-in Station will help get your brand new Rubber tire foam inserts and tires beat up, soft and ready for for the track quickly. Attach your tire to any 12mm hex adapter for a drill and run the tire over the knurled wheels to help soften up your tires. We suggest NOT using wet prepped tires while beating up your tires on the break in station as it can weaken the plastic. The bearings are high grade grease filled bearings that will last a lifetime under these conditions.