All Cisco compatible CWDM XENPAK 40km transceiver modules are certified for functionality, reliability and performance under rigorous testing parameters. Every CWDM XENPAK 40km is RoHS and MSA compliant and built with Tier 1 grade components and lasers. Each Cisco compatible CWDM XENPAK 40km module is individually tested in it's intended application with identical functionality to the OEM product. All ENET CWDM XENPAK 40km modules are backed by an industry-leading lifetime replacement warranty and technical support.