Vibration-isolating handles have been developed for several hand-held vibrating power tools. An attenuation of about 10 dB was obtained for all vibration directions, even at low frequencies, by attaching compound Nighthart isolators to a jack-leg rock drill and a pneumatic grinder, and air cushions to a small rivetting hammer. The isolation systems were designed by simulation, using equivalent electrical circuits for the mechanical impedance of the tool and the human hand, to establish the spring constant of the isolator from the equivalent low-pass filter.