This Cisco QSFP-40G-LR4-S-20 compatible QSFP+ transceiver provides 40GBase-LR4 throughput up to 20km over single-mode fiber (SMF) using a wavelength of 1270nm to 1330nm via an LC connector. It is guaranteed to be 100% compatible with the equivalent Cisco transceiver. This easy to install hot swappable transceiver has been programmed uniquely serialized and data-traffic and application tested to ensure that it will initialize and perform identically. Digital optical monitoring (DOM) support is also present to allow access to real-time operating parameters. This transceiver is Trade Agreements Act (TAA) compliant. We stand behind the quality of our products and proudly offer a limited lifetime warranty.