Originally Posted by
FBinNY
A 6mm key in the RD mounting hole bends the hanger in the identical way. The value of the tool is the gauge capability, not that it has any kind of magic in how it bends.
Not magic per say. But it does a good job and it's fun to use. Besides - if the hanger (which is made out of weaker metal by design so it will bend and break
before the frame does) does break you can yell at the tool. If you do it manually with a hex wrench, then what can you yell at?