LC Keystone Jack Description6 Pack Fiber Adaptor Type: Fiber Optic LC Duplex Couplers; Connector: LC-LC F/F Female to Female Fiber Coupler connect two Duplex LC/LC patch cords together, With screw fixing holes LC modules(with ear) Color: Blue. Multifunctional CompatibilityLC UPC Fiber Optic Adapter Compatible with Various types of optical fiber(SingleMode Multimode 1.25G/10GB OS1/OS2/OM1/OM3 LC Port Universal); These LC-LC Fiber Adapter comply with IEC 61754-4, IEC 60784-14 and TIA 604-3 and conform to RoHS standards. High Return Loss,Low Insertion Loss,Low AttenuationThis LC to LC Fiber Coupler are lightweight due to their plastic bodies. Mating sleeves are made of ceramic, which provides low loss and high signal integrity. As well as connectors, you can identify them by their Blue color. Widely UsedLC Keystone Jack is specially designed for fast Ethernet, Fiber Channel, Gigabit Ethernet Speeds,Local Area Networks, Data Center, Premise installation, Wide Area Networks,C