Standard inner tube from Schwalbe 16x1.75 Auto-AV3 / 47-305, 50-305, 54-305, 57-305, 62-305. Schwalbe inner tubes are reliable. Bicycle retailers appreciate its reliability. Each tire is inflated in the factory and can be tested for air opportunity for 24 hours. The tire maintains its air pressure for longer. In production, Schwalbe requires a very high butyl content and cleanliness of material. For example, the inner tube of Schwalbe retains air pressure significantly longer than other inner tires. This is a system of group insistence treads: an inner tread of Schwalbe is extremely elastic and adapts to several tire sizes. Consequently, they are called inner-tube groups. For example, the inner tube with the number 19A for tire sizes from 27.5" to 29" and for widths from 40 to 62 mm. Finally, the group is 100% completely recyclable. Standard version: high reliability, tested over many years. Valve type: car / writer Valve length: 40 millimeters Weight: 115 grams Tire sizes: 47-305 - 16 x 1.75, 50-305 - 16 x 2.00, 54-305 - 16 x 2.10, 57-305 - 16 x 2 125, 62- 305 - 16 x 2.50, 47-305 - 16 x 1.90