Crucial 4GB DDR3 1333 (PC3 10600) Memory for Apple Model CT4G3S1339M System Specific Memory - Newegg.com
Crucial DDR3 module 4 GB SO DIMM 204 pin 1333 MHz PC3 10600 CL9 1.35 1.5 V unbuffered non ECC for Apple iMac Mac mini Mid 2011 MacBook Pro Early 2011 Late 2011 - Office Depot
Crucial 4GB (BLS4G3D1339DS1S00) Ballistix Sport DDR3 1333 MT/s (PC3-10 – Mega Micro Devices Inc.
Crucial 4GB DDR3L-1333 SODIMM Memory for Mac - CT4G3S1339M" - Walmart.com