Crucial CT4G4SFS8213 is a 4GB DDR4 2133MT/s CL15 SODIMM memory, speeds start at 2133 MT/s and increase bandwidth by up to 30%. It's designed to help your system run faster and more smooth which is one of the easiest and most affordable ways to improve your system's performance. It allows a short-term data access like loading programs faster, browsing the Web or editing in seconds.