The 1.9L.... and 2.1L alternator bracket fix. With time, stuff like metal fatigue, out out of balance ALT can "Break" the lower main bracket, yes, they do break, why, i'm not shure but they do and often, that fix help reinforce the week OEM bracket. . That fix is easy to do, i just took one  of the same upper part and made a lower one out of this one.