The passenger tire was low on air and a small nail was found to be causing a slow leak. Pulled out the nail, but the nail made a hole too small to use a reamer. I had to drill a bigger hole with a 1/8 bit. After that you could use the reamer. Plugged in the tire as instructed and boom, job done. Maybe they could have invested a little more in a better razor and carrying case, but hey, the product works.