This is a 256mb stick of RAM that is PC100 100mhz. This will only work on laptops that take PC100 memory or the laptops listed below...

Compatible Laptops:

Latitude ---- CPx H, CPx J, CPt, C600, C500, C800, LS, L400

Inspiron ---- 2500, 2600, 3500, 3700, 3800, 4000, 5000, 7000, 7500, 8000