Schwalbe tubes are designed and manufactured to retain air pressure considerably longer than their competitors. Not only is each individual tube inflated and inserted into a mould to ensure that there is even wall thickness and excellent air retention, they are also stored under pressure for 24hrs to test air retention.

Will fit the following tire sizes:

40-559 26 x 1.50
47-559 26 x 1.75
50-559 26 x 2.00
54-559 26 x 2.10
57-559 26 x 2.25
60-559 26 x 2.35
62-559 26 x 2.40