Worried about the same tire pressure? Like many Americans, I suffered. The air pressure on the outside of my mower's tires was almost the same as the pressure inside my tires. I had nowhere to go, but I won't suffer anymore! With these little beauties I can create a pressure difference large enough to round my tires again, in fact my tire pressure is now almost 20 pounds above atmospheric pressure! Thank you random Chinese rubber hose factory, you really delivered.