The product is a lot of four SK Hynix 16GB 2Rx8 DDR4-3200AA PC4-25600 laptop RAM memory modules. These modules are in SO-DIMM form factor, DDR4 SDRAM type, with a total capacity of 16GB per module. They come with a lifetime manufacturer warranty and have a bus speed of PC4-25600 (DDR4-3200). These memory modules are suitable for laptops and provide ECC memory features for error correction.