XS+31LC40D is a singlemode SFP/SFP+/SFP28 module with a maximum throughput of 25 Gbps, supporting also lower speeds of 1 Gbps and 10 Gbps with a wavelength of 1310 nm and two LC connectors for connections up to a distance of 40 km. The module is compatible with all active elements from MikroTik and also with devices from other manufacturers "cisco compatible". A perfect choice, for example, for MikroTik device CCR2004-1G-12S+2XS.