This article explains what Duplex LC connectors are, how they work, the difference between single-mode and multimode use, how to choose and maintain them, and why they remain central to fiber network design. LC stands for Lucent Connector, named after the company that first. Fiber connector types LC, SC, FC, ST, MTP, and MPO are widely used in past and present. Form. The LC is a small-form-factor connector system for fibre optic cabling in telecommunications systems, data centres and LANs. LC/APC plug connectors have an obliquely (8°) cut fibre endface that. Multimode Duplex LC Connectors Fiber Optic Connectors are available at Mouser Electronics.