The Signature Line 4GB DDR3 PC3-12800 240-Pin DIMM Memory from Patriot is a dual rank, double-sided module , designed to run at 1600 MHz frequency (PC3-12800) with a CAS latency of 11. Patriot Memory’s Signature Line DDR3 Non-ECC Unbuffered memory delivers the quality, reliability and performance expected for today’s computer needs. Built using specific build-of-materials (BOMs) we ensure that every module meets and exceeds industry standards: offering you a hassle-free upgrade. We certify every component that goes into our modules, including the modules themselves, which must pass strict standards to ensure compatibility, quality and reliability. With free customer service and a lifetime warranty, Patriot Memory’s Signature memory modules are a perfect system upgrade option.