Networx(tm) Fiber Optic Keystone Couplers provide the ultimate performance at a competitive price. Fiber Keystone Couplers from Networx(tm) will live up to expectations time and time again while being pushed to the limits by even the most data hungry applications. Fiber Keystone Couplers offer a great solution when needing to run any length of fiber. By running fiber in the walls and out of the way you can be certain that the fiber will be safe from being crushed and broken. Networx(tm) Fiber Keystone Couplers are available in a variety of connections, multimode, singlemode, simplex and duplex.