The product is a set of two Hynix 2GB 2Rx8 PC3-8500S-7-10-F2 DDR3 RAM SODIMM modules, providing a total capacity of 4GB. These memory modules are suitable for laptops and are designed with non-ECC unbuffered technology - I took them out of my Macbook pro mind 2009 (I haven't tested them since, but they working when I took them out and have sat on a shelf since).