Greetings, I have seen a few posts about the feather touch tension tool.
Most say it is too big to fit in any keyways and is useless.
I took mine and squeezed the tip in a vise just a tiny bit until it fit in
a kwikset deadbolt and it now has an ever so slight taper to it that makes it
wedge into several other brands and does a great job , very sensitive.
I could even go a little more with it to make it smaller but I like it where it is
and would not want to break the solder joint.
I suppose if you have no vise you could use vise grips if you are careful.
Don't throw yours away until you try this.