If you don’t want to spend a lot of time patching a tube while out on a ride, you should carry a spare tube. The ETRTO size is printed on the sidewall of most tires. The first two digits indicate the tire width, and the following digits indicate the tire’s inner diameter. Schwalbe’s No. 13 tube is the right choice for 26-inch tires. The No. 13 features a 40 mm Schrader AV valve.

Information on EU Regulation GPSR 

Name of the manufacturer: Ralf Bohle GmbH
Postal address of the manufacturer: Otto-Hahn-Str. 1, 51580 Reichshof, DE 
Electronic address of the manufacturer: info@schwalbe.com