The 01-HD/HDDM attritor features a variable frequency drive to enhance versatility. The hybrid design combines the features of the 01-HD laboratory/research attritor with the small media capabilities formerly only available in the 01-HDDM model. The key is the addition of an electronically controlled, variable frequency drive motor, which allows for speeds from 400-4000 rpm. The new drive includes a digital readout for rpm, amperage and the percent of torque. The unit is available with a variety of tanks and shaft assemblies for numerous grinding and dispersing applications.