The SK Hynix HMT351S6CFR8C-PB 4GB 2RX8 Laptop Memory is a DDR3 SDRAM memory module with a total capacity of 4GB per module. It features a SO-DIMM form factor and 204 pins, making it compatible with laptops and other devices that require this type of memory. With a bus speed of PC3-12800 (DDR3-1600) and ECC memory features, this module offers reliable performance for various computing tasks. As a product from the trusted brand Hynix, this memory module is a reliable choice for upgrading or replacing existing memory modules in laptops and other devices.