This is a high-performance 800Gb/s dual-port OSFP optical transceiver that supports 2 400Gb/s (2xFR4) connectivity over single-mode fiber. It features two independent OSFP transceiver engines, each utilizing an LC duplex optical interface with four 100G-PAM4 optical lanes, delivering a total of eight 100G electrical lanes across the module. The transceiver implements 2xFR4 technology using 100G-PAM4 electrical and optical modulation over the industry-standard CWDM4 1310 nm wavelength grid, providing reliable, high-bandwidth connectivity for modern data center networks. Designed for long-reach applications, the MMS4X50-NM-OPC supports transmission distances of up to 2,000 meters over single-mode fiber, including links with up to two optical patch panels. The module automatically detects and supports both InfiniBand and Ethernet protocols. Its dual-transceiver architecture allows each OSFP module to deliver two independent 400Gb/s links. The MMS4X50-NM-OPC is ideally suited for high-speed switch-to-switch interconnects in AI, HPC, and cloud data center environments where link distances of up to 2 km are required. A distinctive bright green marking on the transceiver housing identifies the module as the 2 km FR4 variant for easy field identification.