Comes in the following combination:
8GB kit (4GB x 2pcs)
16GB kit (4GB x 4pcs)
32GB kit (8GB x 4pcs)
OWC PC3-10600 DDR3 1333MHz SO-DIMM 204 Pin CL9 SO-DIMM Memory Upgrade Kit for 2011 21.5" & 27" iMac Models, Mid 2011 Mac mini models.
Warranty: Memory comes with Lifetime warranty.