
For all reviewers who think this product is defective, you need to understand what you bought. I've read "they leak", "they don't hold air both ways", "the air just blows", "there is no check valve" and so on (and so on). This device is OPEN FLOW! Read product information! OPEN STREAM is written in several places. Open flow devices are designed to be used with an inflator gauge. (It has a partial list of all the pump sensors you can use). With this device and inflation sensor, you can add air, measure air pressure, and remove air simply by sliding your thumb over the inflation sensor. And that very quickly. Read more about these products! professionals use it!