Alex rims have been around for years my man...they make bmx rims too
they are a box section rim similar to sun rims...good if you run a 2" tyre or more so you get a bigger profile on the ground....instead of the narrower rims that will round the tyre profile.......they came off a 2005 kona shred/scrap/hoss..if that means anything to you...they are on my sex one in the link..have a scroll through
I always run alex rims as they seem to keep their new look for longer than mavic/sun/dt swiss etc....I've ridden trials/dh/used to be a dirt jumper to.....very rarely damaged a wheel mind
ran them on
4 orange patriots
1 orange 222
3 24/7 darkangels
1 Azonic evo
1 giant faith
1 sc chameleon
there are more that I cant remember right now
they're on a par with mavic 325 rims now.....just a few grams heavier
hope this helps