I just bought this the other day and thought I probably wasted money for a new toy I didn’t need until my chain needed a repair on a short ride today. The first ride with this in my pack and it saved my butt. Easily separated the master link and had a spare inside to keep me rolling. Weighs nothing and doubles/triples? as a tire lever and valve core remover. I was already bummed I missed a bigger ride today since I had to take my daughter to the doc this morning and when I got back my wife gave me the green light to pedal a bit. Only a few minutes into my ride my chain came off and was caught behind my cassette so I used this to get it sorted out without muscling it and making things worse. Took me 3 minutes to get rolling again. 10/10 would buy again!