I have tried this "tool" on two tires several times. a motorcycle tire and an ATV trailer tire. Both tires are tubeless and both tires were new at the time of the puncture. I purchased this replacement pack of plugs after having had no success with the batch supplied. First, the plugs themselves are very sticky and barely get into the insertion tool, even if you clean it with the supplied tube. Cleanser. On my first and second try, the brass tip broke off the fork, rendering the fork unusable. Plan B was to simply insert the connector into the insertion tool using the rubber connector itself, leaving the brass tip alone. After wrestling with this for a while, the fork went into the tool, although it left a sticky gummy mass on my fingers and the tool. Every time I took a tool and stuck it in the tire and then pulled it out, the brass tip broke off and fell into the tire leaving a rubber plug in the tool. It has never worked on a bus. I just threw away all the useless tools. What a waste. I'm not a mechanic but I work and service all my equipment from tractors to motorcycles to ATVs. I live in an area where I have to travel a long distance for any type of service, so confidence is a must. This is NOT a tool anyone needs in their arsenal. Period.