light pump / Inflator

When pumping up the bicycle tyres,very often,we don't know how much volume gas is approariate,to solve this problem we design this pump has showing function. As we pumping,the pressure in the tyres increase and this situation will be show on the LED screen.As the progress bar going,we can see when is the time to stop pumping.The electricity of the LED display is coming from the force when we pumping.