The OCZ 4GB (2x2GB) DDR2 SDRAM PC2-8500 Reaper Series Black DIMM is a high-performance memory module designed for upgrading computer systems. With a total capacity of 4GB spread across two 2GB modules, this RAM offers fast data transfer speeds at 1066MHz. The DIMM form factor allows for easy installation, while the DDR2 SDRAM type ensures reliable performance. Made by OCZ, a trusted brand in the industry, these memory modules are a reliable choice for enhancing your computer's speed and efficiency.