The tyres can be pumped with a handpump or even a pump for car tyres. The valve can be pushed to the outside for better access. After removing the cap of the valve and attaching the pump to the valve, you can fill the tyres with air. The front wheels can be filled to 4.5 Bar or 65.3 PSI and the back wheels can be filled till 2.5 Bar or 26.3 PSI. The Performance comes with a small mini-pump, which you can keep in the pocket of the walker with the footrests. But this is more of a travel item and doesn't have a pressure gauge on it - it's best to use one with a pressure gauge like some bike pumps have.