OWC 16 GB Kit (4x4G) 1.35V ECC UR DDR3-1866 ECC...

Macintosh 16 GB Kit (4x4G) 1.35V ECC UR DDR3-1866 ECC Unbuffered DDR3 DIMM 4×4 Kit 16 GB modules are not compatible with 4 and 8 GB modules and cannot be mixed. 4 sockets