An acetal plastic spacer at the center of these couplings insulates bearings, encoders, and other shaft components from stray electric current. Use them with servomotors, which sometimes generate current that travels down the shaft and can damage circuit boards, interfere with readings, and cause wear on bearing raceways. Like other servomotor couplings, they're good for high speeds, precise positioning, and frequent starts and stops. They have zero backlash, which means they transfer power with no delays or wasted motion. A pair of disc springs—one on each side of the spacer—allow the coupling to flex and accommodate for all types of misalignment. Clamping screws secure both shafts with an even, nonmarring grip.