Rokee's RL series metal diaphragm couplings are independently developed on the basis of high-quality products from Europe and Japan. It has smaller volume, larger torque of the same type, more reasonable proportioning size, large compensation range, light weight and small moment of inertia. Special elastic gasket design is adopted in the hole connection part of bolt and diaphragm group, which greatly reduces the stress concentration in the hole edge part, eliminates the tear loss of diaphragm, and extends the service life. With modular design, the coupling assembly is simple and its maintenance and replacement are quick. The performance far exceeds the national standard JM series products, which are widely used in fan systems, steam turbine units and other important industrial fields.