Hey guys was going to replace my HD in my MacBook when i couldnt remove the HD from the Enclosure casing that has the tab attached to. There are 4 black screws that have "star" shape screw. I've been on apple site and looked everywhere and i dont know what size i need for that. I tried a flat head that fit and was able to get two of them off but on the other side it wouldnt budge.. Any Help guys?