Continental's high quality Mountain Tubes are subject to stringent quality control. We love the reliability and durability of these tubes, and they are a staff favorite. Seamless design and vulcanization ensure uniform roundness and enhanced strength around the valve stem. Conti's tubes feature a mid-length, threaded 42mm valve stem and a removable valve core for easily adding sealant when you need puncture insurance. These tubes offer a broader range than most, and are designed to start compact and safely stretch as required to the upper limit.