LC Duplex Coupler Extends Length of Fiber Optic Cable Run Tripp Lite's fiber optic LC coupler connects two 62.5/125 or 50/125 multimode fiber cables with LC connectors to extend the length of the cable run. The duplex adapter accepts two simplex connectors or one duplex connector. Mounts in a Keystone Patch Panel or Wall Plate This LC to LC fiber coupler is designed to snap easily into a keystone patch panel or wall plate. This allows you to route cables through walls and provides a convenient connection to your fiber network. Lifetime Limited Warranty This multimode fiber coupler comes with a lifetime limited warranty.