This hub has a 12mm bore, 56.0mm OD, and 15.0mm length.
0mm, Aluminum,MCPRS56-12-A It is compact and can fit in smaller envelopes than equivalent single beam or double insert Controlflex styles. Ruland supplied Controlflex couplings are a lightweight, low inertia, and zero-backlash coupling designed for use in encoders, tachometers, resolvers, and light duty power transmission applications. The use of one insert allows for higher misalignment capabilities than double insert styles.