Continental Tour Hermetic Plus Dunlop 40 Mm Inner Tube. A Continental bicycle tube is predominantly made of Butyl rubber. Butyl is a very elastic and airtight synthetic rubber. This high elasticity Continental tubes allows a wide range of different tire sizes to be covered.Specifications:- Wheel size (inch): 28- Valve type: Dunlop/Blitz valve- Valve length: 40 mm- Valve diameter: 7.7 mm- Maximum valve pressure 6 bar (Keep the maximum tire pressure in mind)This inner tube is suitable for tires with INCH size:- 26 x 1.40- 26 x 1 5/8 x 1 3/8- 26 x 1.50- 26 x 1.60- 26 x 1.625- 26 x 1.75- 26 x 1.80- 26 x 1.85- 26 x 1.90- 26 x 1 1/2 x 1 3/8- 26 x 1 3/8 x 1 ½- 26 x 1 5/8 x 1 2/2- 26 x 1 5/8- 27.5 x 1.40- 27.5 x 1.50- 27.5 x 1.65- 27.5 x 1.75This inner tube is suitable for tires with the ETRTO size:- 37-559- 40-559- 42-559- 44-559- 47-559- 37-584- 40-584- 44-584- 47-584- 40-590- 42-590This inner tube is suitable for tires with the French size:- 650B- 650 x 35B- 650 Standard- 650 x 38B- 650 x 42B- 650B ½ Ballon- 650 x 38A. tradeinn Bikeinn