These days, with gas stations paying outrageous sums just to (badly) inflate tires, everyone needs one. The reader also works great and inflates in just a minute or two. I needed 4 tires, one of which was almost completely deflated. Only up to 36 so not too big but I was able to make them all without overheating this little one. My favorite features are that it gives you a constant reading as you inflate and then stops when it hits the target. Please note that the cable is short. I have a small hatchback and the outlet is right in the middle, but I still had to stretch as far as I could to get to the right rear wheel. For those with larger cars/trucks, you'll likely need to use the outlets that most of these vehicles have in the back or in the trunk. If you don't have one, you're out of luck as the cables are built in.