Uh, it's a tool but it's park tools so you can go wrong.
After getting Park Tool AWS-1, I realized that I had some hex heads that needed smaller wrench sizes. This tool fit the bill perfectly. So far it has been durable with the jobs I worked on, though I would caution to not overdo it as I expect the smaller hex wrench may strip or break on you if you apply too much torque. A nice addition to my bike toolbox.
I've been using the 4,5. 6mm version for years and finally bought this one due to the proliferation of small Allen screws on brakes and derailleur systems. It's typical Park quality and works great - no surprise there.
get 1 if they are on sale
These are nice for some things, but a lot of times the triangular shape does not allow you to get into tight locations. I find they don't work more often then they do.
