I ordered a serpentine belt tensioner, had the correct part number, picture matched on the site, bought it and got some other tensioner in the correct box with the correct part number on it. I didn't open it up until I needed it two months later, that's when I found out it was the wrong one. I haven't gotten back to them yet on it, but I think I better soon...
The funny thing about science is that if you change one miniscule parameter you change the entire outcome to the way you want it.
