You don't mention what model MBP you have, or whether you bought the MBP or the battery from Craigslist, but I wouldn't trust or recommend any non-Apple battery, due to the number of problems reported with "knockoff" batteries. Also, there is no assurance that knockoff batteries have the same charging technology that Apple uses, involving the battery, the MagSafe adapter and the Mac's logic board.i have the battery in my laptop but its not reading it on my macbook pro....im wondering what the issue is because i bought this off of craigslist and want to make shire this can be a quick fix....any ideas, or experiences? I am running 10.7.3 2.4 i5 dual core 4 gigs ram 500hd