Flat tyre on the track it neednt slow you down the cnc lathed race flex hv pumps compact and shifts air fast up to a maximum pressure of 80psi the ez head works with presta and schrader valves and theres even a retractable hose cnc lathed pump for high volume ez head for presta and schrader valves retractable hose handle locking including bracket 80 psi max 21cm long