E2000 fiber optic adapters are made to fit the E2000 optical fiber connectors developed by Diamond, this kind of fiber optic connector is a relatively new type but it is more and more used today, because the E2000 fiber optic adapter and E2000 cables have many advantages over other fiber optic connector types, for example, the spring-loaded shutters protect against dust and scratching, yet E2000 is an expensive fiber optic products.