I put them on and they were great for two weeks. Then one morning I go out and find that my tire is flat. After inflating the tire everything seemed fine until the next day the same tire deflated. I refilled it and flipped the tabs. After that everything was fine, but I needed new tyres. After getting the new tires I put the tongues on and the next day my tire was deflated again. Each time I checked to make sure the device was screwed tight and tight. Good idea, bad design.