TRENDnet's LC Duplex Fiber Optic Keystone Coupler Jacks ? 5-Pack, model TC-K05LC, includes five LC duplex fiber keystone jacks for use with TRENDnet's TC-KP24SA blank shielded keystone patch panel. These fiber keystone jacks are designed for gigabit and 10G fiber optic network applications. Each fiber keystone jack is designed for use with single-mode or multi-mode fiber cabling. The LC fiber female-to-female coupler design makes it easy and simple to join two fiber patch cables together. These LC duplex fiber coupler jacks feature a convenient tool-less snap-in design for easy installation.