What is the Huawei TN21MR402?
The Huawei TN21MR402 is a circuit board, listed by the manufacturer as "WDM TN21MR402 4-CHANNEL OPTICAL ADD/DROP MULTIPLEXING BOARD 192.5/192.6/192.7/192.8THZ 107.76 MM HEI". It is part of Circular Telecom's surplus and refurbished telecom/IT equipment inventory.
