Oldham type flexible coupling LK4 series Oldham type flexible coupling LK4 series includes set screw type (Oldham) and clamp type (Oldham). Body material is aluminum alloy. Set screw type (Oldham)shaft coupling keeps following features: 1. Oldham type flexible coupling; 2. zero backlash; 3. allows high parallel and angular misalignments; 4. high torsional stiffness and response; 5. simple configuration enable ease of assembly; 6.setscrew type.