Specially designed ridges allow these bellows couplings to compensate for more misalignment than other precision couplings—useful for low-torque, high-precision applications such as instrumentation and motion control. They also allow zero backlash (no play) and never need lubrication. Couplings are nickel and stainless steel so they can be used in mildly corrosive environments. Fasten to your shaft by tightening the set screws, which bite into the shaft to hold it.