The product is a lot of four 4GB 2RX8 PC3-10600U-09-11-B1 Micron DDR3 SDRAM memory modules, with a total capacity of 16GB. Each module has a capacity of 4GB and is designed in a DIMM form factor with a bus speed of PC3-10600 (DDR3-1333). The modules have 240 pins and are approximately 7.1 inches long, 3 inches wide, and 1.3 inches high. The model number is MT16FTF51264AZ-1G4M1. Ideal for upgrading or replacing memory modules in computers requiring DDR3 SDRAM type memory. Tested and working.