I bought one from Aventon. It was easy to repair and didn’t require anything special.

What is wrong with it? I’ve been using it for years and it does what it’s supposed to do.

Al is a major element in the solar system. Most rocks have Al2O3 on the order of 3-10 wt.%. That includes chondrites (the major class of meteorite) which have plenty of feldspar, a mineral that’s like 20 wt.% Al2O3, and calcium-aluminium inclusions (CAIs), which are as their name suggests, Al-rich.