What is the Sandstone QFP400-L4-0ELS-10K?
The Sandstone QFP400-L4-0ELS-10K is a QSFP optical transceiver module, listed by the manufacturer as "MSA Compatible 400G QSFPDD, 400GBASE-LR4, 1310 nm, 10km SMF LC, DDM, C-Temp, BLUE Latch, With FEC". It is part of Circular Telecom's surplus and refurbished telecom/IT equipment inventory.