The Crucial 4GB SO-DIMM Memory Module is a high-quality DDR4 SDRAM RAM module with a total capacity of 40GB spread across 10 modules, each with 4GB of capacity. This memory module is designed for use in computers and laptops, and features a SO-DIMM form factor with 260 pins for easy installation. The Crucial brand is known for its reliable and durable memory products, making this module a reliable choice for upgrading your computer's memory capacity.