AIRLESS SOLID TUBE 40-622 SAS01.01 Schwalbe The core of the airless system is the newly developed airless tube, made of expanded thermoplastic polyurethane (E-TPU). This material has four key properties: excellent elasticity, excellent resilience, high abrasion resistance, incredibly durable, even in heat and freezing cold. The Solid Tube Airless from SCHWALBE is the core of the innovative Airless system - specially developed for e-bike use in the city up to 25 km/h. The inner tube is made of expanded thermoplastic polyurethane (E-TPU) and combines four key properties: exceptional elasticity, excellent resilience, high abrasion resistance and extreme durability - even in the heat or freezing cold. It therefore offers a maintenance-free alternative to the classic pneumatic tube - without compromising comfort and reliability. ETRTO 40-622 Features for e-bikes up to 25 km/h Main color white Secondary color blue Type/kind Accessories Wheel size 28 "