All Cisco compatible DWDM SFP transceiver modules are certified for functionality, reliability and performance under rigorous testing parameters. Every DWDM SFP is RoHS and MSA compliant and built with Tier 1 grade components and lasers. Each Cisco compatible DWDM SFP module is individually tested in it's intended application with identical functionality to the OEM product. All ENET DWDM SFP modules are backed by an industry-leading lifetime replacement warranty and technical support.