What is the Sandstone QSFP-100G-ER4L-J-ST?
The Sandstone QSFP-100G-ER4L-J-ST is a QSFP optical transceiver module, listed by the manufacturer as "Juniper Compatible 100G QSFP28, 100BASE-ESR4-LITE, 1310mm, 40KM, SMF LC, DDM, C-Temp, Red latch, single rate version W/FEC". It is part of Circular Telecom's surplus and refurbished telecom/IT equipment inventory.