These Presta valve stems are compatible with tubeless rims and tires for road, gravel, mountain, and fat bike wheels. The kit includes two Presta valve stems, two machined aluminum caps, two nuts, two extra valve cores, a unique machined aluminum valve core remover, and three rubber base options for compatibility with more rim internal shapes. 44mm stem length Slotted stem base for compatibility with tire inserts Oversized stem nut for better sealing and easier removal Stem threaded below rubber seal for better performance on single wall rims Three rubber bases included: two types of cones (one installed), one channel SPECIFICATIONS Weight: 9g The Story Wolf Tooth was founded to design and manufacture precision cycling products that emphasize function, performance, and reliability to meet the needs of our fellow racers and riders. We are a group of cyclists in Minneapolis, Minnesota that spend a lot of time talking about bike components. Like most detail-obsessed riders, we're always looking for new products that could make our bikes lighter, faster, more versatile, or more reliable. We pride ourselves on delivering premium products of the highest quality.