3.50-10 Angled valve stem Classic Euro-scooter size 3.50-10 inner tube with angled valve stem Fits tires with a 10″ rim diameter 30 Day Warranty Description 3.50-10 inner tube with angled valve stem. Fits tires with a 10″ rim diameter. 3.50-10 is the classic tube and tire size for the many “Euro-scooters” from the 1960s through the ’90s, such as Vespas and Lambrettas. It is also used on some currently made “retro-style” scooters like the Stella. In addition to their use on classic-styled motor scooters, this size may also find a home on certain mobility scooter models such as the Afikim Afiscooter S3 and S4 series.