The Samsung 1GB (2x512MB) 2rx16 PC2-4200S-444-10-A3 M470T6554BZ3-CD5 is a memory module kit that consists of two SO-DIMM modules with a total capacity of 1GB. Each module has a capacity of 512MB and operates at a bus speed of PC2-4200 (DDR2-533). This DDR2 SDRAM memory module is designed for use in computers. It is manufactured in the Philippines by the brand Samsung. This memory module provides reliable and efficient performance for upgrading or replacing existing memory modules in a computer system.