Shaft couplings, collars, and universal joints connect two shafts. They transmit power and help protect against shock, vibration, misalignment, backlash, and overload. Flexible couplings dampen vibration and compensate for minimal shaft misalignment. Precision motion control couplings provide zero backlash for precision control applications, such as robotics, stepper motor, and servo motor applications. Rigid couplings and shaft adapters transmit maximum torque with minimal vibration damping. They are suitable for applications where direct, properly aligned connections are required. Universal joints connect two shafts which are offset at an angle, allowing smooth operation without stressing the shafts, or coupling.