This is a Cisco QSFP-1G-CU5M compatible 1GBase-CU QSFP28 to QSFP28 direct attach cable that operates over passive copper with a maximum reach of .5m (1.6ft). It has been programmed, uniquely serialized, and data-traffic and application tested to ensure it is 1% compliant and functional. This direct attach cable is TAA (Trade Agreements Act) compliant, and is built to comply with MSA (Multi-Source Agreement) standards. We stand behind the quality of our products and proudly offer a limited lifetime warranty.