The V-10 valve is a non-return type of valve, fitted with a protective valve screw. For inflation, the screw has to be removed. Air is blown into the valve, and the valve screw has to be set back in place in order to fully secure any loss of air from the valve. The valve is equipped with a non-return flap that secures the air when inflating.The V-40 valve is designed for easy inflation and deflation of our largest products. This isnota non-return valve. To inflate the product, the valve is opened by turning the valve screw anti-clockwise 3-4 times (do not remove the screw). Inflate through the center hole of the screw itself, and tighten the screw.To inflate, you can use a hand pump, but preferably an air compressor with a blowgun or – if you have a Polyform inflation adapter – with a tire nozzle.