Plugging device drives the plug into the hole with a twist of the Allen wrench; plug then expands under pressure to fill the punctured area; a firm pull on the stem seats the mushroom head on the inner wall allowing no air to escape. Easily installs mushroom-shaped rubber plugs into all tubeless tires on the wheel. For tubeless tires. Kit includes:. Plugging device. Nozzle adapter. Rasp tool. Probe tool. Retractable razor blade. Allen wrench. 15 - mushroom plugs (5/16" diameter x 3/4" long stem). Laminated instructions. 3-1/2" x 7-1/2" x 1" zippered pouch. Total weight only 12 oz.