The least expensive way to ditch 40+ grams of rotating weight is with our Turbo Talc Tubes. A patented oversized 4.8cm valve base prevents tearing while a partially threaded valve stem provides a clean interface with pumps. Our lightest and most supple tube offering it's also been proven in rolling-resistance testing to reduce drag by as much as 13% per wheel. Specialized Turbo Presta Valve Tube with Talc Bicycle Tire in Black