Cush Core Mixed Pro Set (29" & 27. 5")Improving Your Ride Quality Cush Core is an engineered foam insert that mounts inside a bike tire. It divides the inner volume of the tire in half, with air underneath the tread and the Cush Core insert next to the rim. The purpose of Cushcore is to improve the ride quality of your bike. It is not just for flat protection. Cush Core absorbs shock, stops deflection off obstacles, reduces vibration, and stabilizes the tire against roll and squirm. Think of it as suspension for your tires designed to give you a faster, smoother ride. This system is designed to be used with tubeless-ready or tubeless converted mountain bike rims and tires. Cush Core is compatible with tubeless tire sealants. This kit comes with a 27. 5" and 29" insert, two 44mm Cush Core Presta air valves, a valve core tool, installation instructions, and rim stickers. Features The Cush Core Pro fits tire widths from 2. 1" to 2. 6" tires and inner rim widths from 22mm to 35mm Reduces vibrations and stabilizes the tire against roll and squirm Comes with a 27. 5" and 29" insert, two 44mm Cush Core Presta air valves, a valve core tool, installation instructions, and rim stickers | Cushcore | Mixed Pro Set (29" & 27. 5") 29" & 27. 5"