Optical Fiber Cuffs are designed to perform optogenetic excitation/inhibition on muscles and/or nerve fibers.  Light and flexible plastic optical fibers terminated with an angled mirror (MA45 tip) allow multiple illumination spots around fibrous tissues. Our design provides a polyimide based cuff composed of two half-cylindrical parts that can surround the muscle or the nerve. At the opposite end, all fibers are bundled into a standard ferrule to allow connection to a patch cord.