Move 40 GbE traffic across longer distances with the StarTech QSFP40LR4ST 40GBASE-LR4 QSFP+ module. Built for single-mode fiber environments, it is the right class of optic when short-reach transceivers are no longer enough and the network needs to span between rooms, rows, or buildings. The LR4 design supports enterprise optical planning where reach, link stability, and standards alignment matter. For teams maintaining aggregation, core, or interconnect layers, this module helps preserve a clean 40 GbE architecture while extending the physical footprint of the network. It is a practical choice for infrastructure groups that want to avoid redesigning switching infrastructure just to gain distance. Because it is an MSA uncoded module, it fits into procurement strategies that prioritize interoperability and controlled optics selection. That matters when the cost of a mismatched transceiver is measured in troubleshooting time, not just hardware spend. For organizations running 40 GbE on single-mode fiber, this optic offers the reach profile that justifies its place in the bill of materials.