Patriot Memory's Signature Line DDR3 1333MHz SODIMM for Apple computer systems delivers quality, reliability and performance that makes them the perfect memory upgrade solution. We test for compatibility in Apple iMac, MacBook, MacBook Pro and Mac Pro systems. This 8GB kit (2 x 4GB) is designed to run at PC3-10600 (1333MHz) at CAS 9 latency timings. Built using specific build-of-materials (BOMs) we ensure that every module meets and exceeds industry standards: offering you a hassle-free upgrade. With free customer service and a lifetime warranty, Patriot Memory's Signature memory modules are a perfect system upgrade option.