In response to a growing number of requests, Helical has designed a series of close-tolerance precision couplings that are also adaptable to low inertia requirements. Series 3000 and 4000 are stainless steel; series 5000 and 6000 are aluminum alloy. Please note that the set screw unit (D) and the integral clamp unit (E) each offers standard shaft tolerances of .0005 in. Contact our engineering department for details.