The G.Skill 4GB PC2-6400 DDR2 800 Desktop PC Memory Kit includes four 1GB DIMM modules specifically designed for desktop computers. With a total capacity of 4GB, these DDR2 SDRAM modules offer fast data transfer speeds at 800MHz. The modules have a bus speed of PC2-6400 and are manufactured in the United States. This memory kit is a reliable option for upgrading your computer's RAM capacity and improving overall performance.