The product is a set of two 1GB Nanya memory modules designed for Apple MacBook 2009. These DDR2 SO-DIMM SDRAM modules have a total capacity of 2GB (4GB in total) and are registered and fully buffered. The memory modules have a form factor of SO-DIMM, a bus speed of PC3-12800 (DDR3-1600), and have ECC memory features. With 204 pins, these memory modules offer high performance and reliability for your computer needs.