The Komputerbay MACMEMORY 4GB Kit includes two 2GB DDR2 modules with a total capacity of 4GB. Designed for Apple computers, this RAM upgrade is lightweight at 1.44 ounces and compact with dimensions of 6.8 x 0.5 x 3.5 inches. The memory modules have a bus speed of PC2-5300 (DDR2-667), ensuring fast and efficient performance for your system. Made by Komputerbay, a trusted brand in computer components, this product is a reliable choice to enhance your Apple computer's memory capacity.