Combining high performance materials, design features and precision, Zero-Max composite shaft couplings withstand the rigors of the most demanding servomotor systems. Machined of ASTM A 108 steel and 6061-T6 aluminum, their body components are inherently balanced. The functioning components are made from precisely oriented and layered composite material. Precise alignment of the assembled components is ensured through ISO Class 12.9 hardened shoulder bolts. All precisely integrated CD couplings design features provide the ideal combination of highly dynamic load capacity and high torsional stiffness to ensure reliable system operation. In addition, the couplings have zero backlash, are good for reversing loads, provide smooth operation at high speeds, and are compact with a clamping design that fits most applications. Standard models and sizes include single and double flex models with clamp style hubs with or without keyways. The torque capacities range from 40 to 1436 Nm and beyond with speed ratings from 4,400 to 17,000 rpm. Environmentally friendly, all CD couplings are manufactured of RoHS compliant materials.