Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Limit Switch a Pleasant Surprise

This inflator is quite convenient, except for the fact that the coupling to the valve stem does not come off easily, losing air in the process. I did not see a product spec. that identified the red "circle" on the inflator as a pressure gauge AND a limit switch, allowing the user to set the desired pressure and walk away, and not have to use a manual pressure gauge to check the tire pressure. This is a feature that I was surprised to find, and pleasantly so.