I found this tool super useful for tightening inputs and outputs on my amp and for the output jacks on my guitars.
I actually bought the tool for putting locking tuners on my strat and th etool didnt actually fit the nut for the fender locking tuners, so I had to use a plyers for that in the end.
Although it didnt fit the nut size i bought it for, I'll still be making use of this on my gutiars and amps and whatever else I find out it fits on.