The product is a matched pair of 4MB, 72-pin, 70ns DRAM SIMMs produced by Texas Instruments. These SIMMs are the TMS44400DJ-70 type, designed for use in computers. Each SIMM contains 4MB of memory and has a form factor that is compatible with the 72-pin SIMM slots found in certain computer systems. These DRAM SIMMs are a reliable and efficient choice for expanding the memory capacity of vintage computers that support SIMM modules.