The ETU-LINK QSFP-DD AOC is an active optical cable capable of speeds up to 400G/s. It utilizes the QSFP-DD packaging module and is based on VCSEL array technology. Thanks to PAM4 signal modulation, each channel can achieve a maximum rate of 53Gbps. Through multimode optical fibers, it provides eight independent data transmission channels and eight data reception channels, enabling a total data rate of 400Gb/s over a 100-meter transmission distance. In addition, this optical cable adheres to QSFP specifications including SFF8436, 8432, 8472, and IEEE802.3bm, offering high performance and reliability. It is widely used for high-speed connectivity needs in data centers.