I was thinking of buying replacement lasers for both my Ps2's, and would like to know which type of laser I should buy. I have: One Fat 3000 series model 2 Slim 9000 series model. Thanks.
Your better off opening up the ps-2's and looking at them. That way you'll know exactly what you need.
Firstly, there is no "3000" series PlayStation 2. PlayStation 2 model numbers have 5 digits. If you mean the SCPH-30000 series, there were many models under it. The earliest ones came with the KHS-400B, while later ones were fitted with the KHS-400C. Some even had the SANYO SF-HD7 installed. This is why it is really recommended for you to not make assumptions, and actually check what optical block is installed. Likewise, unless it is a known fact that the SCPH-90000 series came with only one optical block model, it might not be wise to make assumptions on this part.