Abbey Bike Tools preHAG - 3D Printed Derailleur Hanger Alignment Checker

I was about to take my bike to the shop just to check the hanger alignment—this tool paid for itself in one use. So easy: just pop it on and spin the cranks. Definitely recommend for any home mechanic.

Does the job well and is super quick. The only reason I’m giving 4 stars is that it might not fit every frame/derailleur combo, so measure before you buy. But for my bike it was perfect.

If you do your own maintenance, this is a must-have. It takes seconds to use and gives you confidence that your derailleur is aligned. At $10 it’s a steal.

The idea is great, but it didn’t fit my specific derailleur/ frame. Maybe I should’ve measured first. I’ll have to modify it or send it back. Others seem to like it though.

For the price, you can’t beat it. I've used it on three bikes already and it’s spot on. The 3D printing is solid and the tool is lightweight. A nice addition to my toolbox.

It works and it’s convenient, but I feel like $10 could be lower for a small piece of plastic. Still, it does exactly what it says and saves me time, so I’d buy it again.