The CT4G3ERSDD8186D.18FKD from Crucial is a DDR3-1866 ECC Registered DIMM, designed to increase the performance and stability of servers and workstations. It features a 512Mx72 configuration, equating to a 4GB memory module capable of operating at the PC3-14900 specification. This module uses a 240-pin design compatible with DDR3 1866MHz system requirements. With ECC technology, it ensures data integrity, automatically detecting and correcting internal data corruption, a vital feature for systems managing critical operations. Crucial's reputation for reliability and performance is evident in the manufacture of this module, making it an excellent choice for upgrading or building new enterprise computing solutions.