The TSI-1 enables you to inject the perfect amount of sealant directly into mounted tubeless tires through the valve stem without removing the bead from the rim Long, thin tube is able to fit all the way through many Presta stems with removable valve cores Features an oversized syringe body with easyto-read gauge for precise application of sealant Retailers are not permitted to sell on the Amazon.com marketplace unless authorized in writing by Park Tool