Set of 4 matched and tested. The product is a 4MB NEC MC-421000A32B-70 SIMM memory module, designed for use in computers that require a 72-pin SIMM form factor memory module. This memory module offers fastPage technology for improved performance, making it suitable for enhancing the speed and efficiency of the computer's memory capacity. The NEC brand ensures reliability and quality in this essential computer component, providing users with a dependable solution for upgrading their system's memory capacity.