Genuine Innovations have unveiled the Fat 20 CO2 cartridge.

Designer for fatter MTB tyres, the new cartridge sits between the US company's existing 16g and 25g cartridges.

The Fat 20 will inflate 29er tyres to 43psi, 26" x 2.4 tyres to 32psi and two 26" x 1.95 tyres to 24psi.

Two 20g cartridges will set you back £5.99, six cost £14.99, while 20 retail at £60.00.