Let me start by saying I've been in the auto repair business for 40 years so I can fix hundreds with a plug or patch tire . I also test less than 5% of the products I buy, reserving the effort for excellent service or product, or as a precautionary check for a poor quality product. I bought it to have at home in case a quick repair is needed. A screw came loose in my trailer tire and I unscrewed the kit. While the quality of the instruments themselves was acceptable, the plugs themselves leave plenty of room for improvement. I've plugged the hole 4 times (remember I've done this before and never had to plug the hole again). The reamer in this set is big, maybe too big for the size of the plugs, it may be better to use better quality rope/cord (glue cords for plugs). Plug next to it to stop the leak. With the kit provided, the weak but very sharp knife in the kit was just beginning to cut itself. I ended up taking the tire somewhere to plug it in and it worked. There has to be a better kit on the market.