What is the Brocade 40G-QSFP-ER4?
The Brocade 40G-QSFP-ER4 is a QSFP optical transceiver module, listed by the manufacturer as "Brocade Compatible - 40GBASE-ER4 QSFP+ Optic 30km SMF". It is part of Circular Telecom's surplus and refurbished telecom/IT equipment inventory.