Our GLC-BX80-U is 100% compatible with the original Cisco GLC-BX80-U. We have a large quantity of GLC-BX80-U transceivers in stock and can ship the GLC-BX80-U to you within 24 hours. All of our Cisco compatible transceivers are tested in-house prior to shipping to insure they are in perfect physical and working condition. We guarantee the GLC-BX80-U transceivers to work in your Cisco equipments and all of our transceiver modules come with a lifetime warranty.