Duo efficiency: power saving & performance 33% improvement in handling speed, at 2133Mbps and 17Gbps Extends 25% laptop battery performance with 1.2v Quality structure with tested Compatibilty 100% Compatibility performance Easy installation for the best of stability Frequency: 2666MHz Capacity: 8GB Voltage; 1.2V Cas Latency; CL19 PIN; 260-pin Certificate; RoHS, CE, FCC, RCM, VCCI, JEDEC Package; Single Channel Package