G.Skill 8GB Ripjaws 4 DDR4 2666MHz PC4-21300 CL15 Dual Channel kit (2x4GB) 8GB Dual Channel Kit - 2 matched 4GB modules DDR4 2666MHz memory, PC4-21300 With Red Ripjaws 4 heatsinks Timings of 15-15-15-35 at 1.2V Lower voltage means lower power consumption