The product is a 256MB PC133 SDRAM SO-DIMM Laptop RAM by Hynix, tested and confirmed to be in working order. This single module has a capacity of 256MB and is designed for use in laptops with a 144-pin interface. The memory features Error Correction Code (ECC) for improved reliability. The Hynix PC133 SDR model operates at a bus speed of PC-133, providing efficient data transfer for computing tasks. With its compact SO-DIMM form factor, this RAM module is a reliable choice to enhance the performance and capacity of your laptop.