Timetec Hynix IC Apple 8GB Kit (2x4GB) DDR3L 1600MHz PC3L-12800 SODIMM Memory Upgrade For MacBook Pro 13-inch/15-inch Mid 2012, iMac 21.5-inch Late 2012/Early 2013 (Low Density 8GB Kit (2x4GB)) DDR3L 1600MHz PC3L-12800 204-Pin Unbuffered Non ECC 1.35V CL11 Dual Rank 2Rx8 based 256x8 JEDEC standard 1.35V (1.28V ~ 1.45V) and 1.5V (1.425V ~ 1.575V) Power Supply This is a dual voltage piece and can operate at 1.35V or 1.5V Module Size: 4GB Package: 2x4GB For MacBook Pro 9, 2 (13-inch mid 2012)/ 9, 1 (15-inch mid 2012); Mac mini 6, 1 (Late 2012)/ 6, 2 (Late 2012)/ 6, 2 (Late 2012 Server) iMac 13,1 (21.5-inch Late 2012)/ 13,3 (21.5-inch Early 2013)/ 13,2 (27-inch Late 2012)/ 14,2 (27-inch Late 2013)/ 15,1 w/Retina 5K display (27-inch Late 2014/Mid 2015) Guaranteed  Lifetime warranty from Purchase Date Free technical support (support@timetecinc.com) MON - FRI 9AM-6PM PST