This kit includes the bolts and spacers to be mounted to your bike's fender strut. This kit is included with all new bags, you do NOT need to buy this kit if you are buying new bags. You will need this kit if you are buying used bags, or if you want to be able to mount your bags to more than one bike. Also, note that this kit will not allow you to mount bags on different models of bikes. For example, you can't use this kit to mount Dyna bags onto a Sportster.