Autochuck is another name for the push button spindle/chuck (collet) assembly which holds the dental bur and onto which the other components of the turbine cartridge (e.g. bearings, impeller) are attached or pressed. The ISO maximum specification for concentricity (run-out) is 0.0012 in. / 0.03 mm.
Two common autochuck designs are clamp-pad and wedge.
