The ATOP 400G QSFP112 SR4 transceiver is a high-quality optical transceiver designed for utilization in 400 Gigabit Ethernet links over multimode fiber. This product features 4 independent electrical input/output channels capable of converting 106.25 Gbps (PAM4) electrical input data into 4 channels of 106.25 Gbps (PAM4) parallel optical signals. Additionally, it can also convert 4 channels of parallel optical signals, each operating at 106.25 Gbps (PAM4), into 4 channels of 106.25 Gbps (PAM4) electrical output data.