Dear you who are reading, please spread the word: aluminum 6061 is much softer than 7075. 6061 is much easier to machine with CNC, because of its softness, but the chainrings made from aluminum 6061 alloy last orders of magnitude less, than those made from 7075 aluminum, due to the significant difference in hardness.
I am posting this, and hoping you will spread the word, because I'm up to here with dishonest sellers who take my money for a 7075 chainring and send me a replacement which is made of 6061, even though I clearly stated that I do NOT WANT a chainring made of aluminum 6061.
This particualr seller ran out the clock on me, so I could not start a complaint through the PayPal resolution center (45 days max after the transaction), but I still sent an e-mail to PayPal.
Sellers thrive on general ignorance. Heck, the in-built obsolescence of chainrings made of aluminum 6061 is a GOOD THING from their point of view, as you will be forced to buy a new chainring much faster than if it were made of aluminum 7075 or better yet, steel.