CST Road Bike Tube 700x18/25C FV48mm, FV60mm & FV80mm (Presta) Features: * A CST bicycle tube is predominantly made of Butyl rubber. * Butyl is a very elastic and airtight synthetic rubber. * This high elasticity CST tubes allows a wide range of different tire sizes to be covered. Brand : CST Saiz : 700 x 18/25C Valve : 48mm (99 gram), 60mm (99 gram) & 80mm (103 gram) Head : Presta Please give five stars good reviews for our goods and services. If you have any questions, please contact us on the chat. Thank you for coming.