The product is a Crucial CT25664AA667.M16FH DDR2 PC2-5300U 667MHz DIMM memory with a total capacity of 4GB, divided into two 2GB modules. It is designed for standard profile motherboards with 240 pins and operates at a bus speed of PC2-5300 (DDR2-667). This memory is non-ECC, unbuffered, and lead-free, making it safe and reliable for use in various computer systems. With a CAS latency of CL5, it offers fast and efficient performance for laptops and desktops requiring DDR2 SDRAM memory modules.