4GB kit (2GBx2), Ballistix 240-pin DIMM, DDR3 PC3-10600 Memory Modules, 6-6-6-20, Unbuffered, NON-ECC, DDR3-1333, 1.8V, 256Meg x 64. Ballistix 240-pin DIMMs are found in DDR3 memory. DDR3 - the next generation of memory - boasts an improved architecture allowing very fast data transmission. Ballistix 240-pin DIMMs are available in DDR3 PC3-12800 SDRAM (DDR3-1600). A Ballistix dual inline memory module (DIMM) consists of a number of memory components attached to a black printed circuit board. Gold pins, found on the bottom of the DIMM, provide a connection between the module and a socket on a larger printed circuit board. The pins on the front and back of a DIMM are not connected to each other. To use DDR3, your system motherboard must have 240-pin DIMM slots and a chipset that supports DDR3 - which is a different technology than that of than its predecessors, DDR2 and DDR. DDR3 incorporates different sockets; they are not interchangeable or backward-compatible. The number of black components on a Ballistix 240-pin DIMM can vary, but it always has 120 pins on the front and 120 pins on the back, for a total of 240. Ballistix 240-pin DIMMs are approximately 5.25 inches long and 1.18 inches high, though the heights can vary. These 240-pin DDR3 DIMMs have only one notch within the row of pins, and each technology has the notch in a slightly different location on the module.