8GB DDR3 1333MHz PC3-10600 SODIMM for Apple MacBook Pro 2011 8,1 8,2 8,3. Certified for all 2011 MacBook with Intel Core i5 i7, 13" 15"MD313LL/A, MC725LL/A CTO, i7 2.2GHz 17" MC725LL/A, i7 2.3GHz 15" MC723LL/A CTO, i7 2.2GHz 15" MC723LL/A, i7 2.0GHz 15" MC721LL/A, i7 2.7GHz 13" MC724LL/A, i5 2.3GHz 13" MC700LL/A Apple recommends two matching modules of the same size be installed for maximum performance. MemoryMasters is backed by Lifetime Warranty. Additional Details ------------------------------ Package quantity: 1