Cush Core Pro Tire Insert Set. Features: An engineered foam insert that mounts inside a mountain bike tire. It divides the inner volume of the tire in half, with air underneath the tread and the CushCore insert next to the rim Absorbs impacts, reduces vibration, and adds lateral stability to the tire Third party testing has revealed that compared to a standard tubeless set-up, Cush Core provides a 12% smoother ride, 35% more sidewall stability, 16% less suspension trave consumption, 3% less rolling resistance, and 50% less impact force transferred to the rim This system is designed to be used with tubeless-ready or tubeless converted mountain bike rims and tires, as well as standard tubeless sealant Doesn't absorb sealant like other tire inserts on the market Includes special tubeless air valves that allows air to move through the valve without becoming obstructed by the insert *Tubeless valve not included with single packs Specs: Package:set Wheel Size:27.5" (650b) Plus Width Rim:tire 2.6-3"/rim 30-45mm Weight:290g