If you don't have the tools to change a tire on a rim, this option is a safe way to do the job yourself. The tire is delivered fully assembled and inflated. Simply remove the old hub cap, remove the locking ring and remove the rim and two washers from the axle. Slide one of the supplied washers onto the axle, then the new tire and the remaining washer. Reinstall the locking ring to hold everything together. Use a grease gun to fill the cavity between the inside of the rim and the axle to allow the wheel to spin freely. Slide the hubcap back into place and you're done! If you have needle nose pliers, rags, and a grease gun, the whole job should be done in less than 30 minutes.