Plug in Mod

[SirDinkleBerry]

Hi everyone! I've been comming here off and on and love this site for my backups!

But, now i've ran into a situation. I have an old playstation (the gray, square one). And it won't play my back ups. I went to modchip.com to look for a mod chip for it. They have a plug in one, but i'm not sure if they are reliable and if it will actually permit me to play my back ups. Could some one please advise this nervous soldier?