The Schwalbe Marathon Tires incorporate light-reflecting sidewalls for better visibility and also utilizes a Silica compound for easy rolling and longer life. SmartGuard puncture protection to resist thorns, shards and even thumbtacks Marathon Silica compound for easy rolling and longer life Reflex sidewalls incorporate light-reflecting bands Tire meets ECR R75 certification for e-bike use up to 50km/h Tire Intended Use: Touring-Hybrid ISO Diameter: 584 / 650b / 27.5" ISO Width (mm): 38 mm Labeled Size: 650b x 38 Tire Bead: Wire Tire Diameter: 650b Tire Type: Clincher Weight: 940 Weight (oz): 33 TPI: 67 Flat Protection: Tread and Sidewall PSI: 85 Designed for ebike: Yes