The Patriot Signature Line DDR3 4GB (2x2GB) 1600MHz SO-DIMM 204-Pin Non-ECC RAM modules offer a total capacity of 4GB spread across two 2GB modules. These memory modules are designed for high performance with a bus speed of PC3-12800 (1600 MHz) and are ideal for computers requiring a DDR3 SDRAM form factor. The non-ECC and unbuffered features ensure reliable and efficient memory access, making them a great choice for both gaming and professional applications. With a lifetime manufacturer warranty, users can trust in the durability and quality of these RAM modules.