OSFP 2x400G LR4 transceiver modules are designed for 800G Gigabit Ethernet links over 10km of single-mode fiber. The module has 8 independent channels of electrical input/output, each operating at up to 106.25Gbps. This transceiver consists of two transmitter/receiver units, with each operating on a set of 4 wavelengths on the ITU G.694.2 CWDM grid near 1300nm. The module’s transmitter path contains a bidirectional PAM4 re-timer ASIC integrating an 8-channel modulator driver, 8 externally modulated lasers, and two optical multiplexers. On the receiver path, two optical demultiplexers are coupled to eight photodiodes and two 4-channel TIA arrays, as well as a PAM4 re-timer. The electrical interface of the module complies with the 800GAUI-8 interface defined by IEEE 802.3ck and complies with OSFP MSA.