The ENET DWDM-X2-37.39-40K-ENC Cisco Compatible DWDM X2 transceiver operates at 10 Gbps over Single-mode fiber at 1537.40nm with a maximum reach of 40 kilometers. Each DWDM-X2-37.39-40K-ENC is 100% compatible in fit, form, and functionality compared to the OEM product. Our extensive quality control measures begin with physically inspecting each module, verification of hardware type, wavelength, transmit power, receive power, and full optical monitoring functionality (if applicable). Each DWDM-X2-37.39-40K-ENC is individually programmed in-house and then Spirent® tested for performance and functionality as well as compatibility tested in target Cisco platforms. Old and new revisions of Cisco operating software are used for testing to ensure 100% compatibility. ENET tests each transceiver using Spirent® Test Centers to emulate live traffic through actual reels of fiber ranging in lengths from 100 meters to over 100 kilometers. These extensive performance testing procedures combined with compatibility testing in more than 80 switches, routers, and servers guarantees each and every transceiver performs flawlessly in its intended environment. All ENET Cisco compatible transceivers are MSA compliant for seamless integration and RoHS compliant for environmental conformity. All ENET transceivers are backed by a Lifetime Replacement Warranty.