The Samsung 4GB 1RX8 PC4-2133P-SAO-10 M471A5143DBO-CPB is a DDR4 SDRAM memory module with a total capacity of 4GB and 260 pins. It is designed for use in laptops and other mobile devices, featuring a SO-DIMM form factor and a bus speed of PC4-17000 (DDR4-2133). This module also includes ECC memory features, providing error correction for increased reliability. Made in China, this memory module is a high-quality and reliable option for enhancing the performance of your computer or tablet.