#brake_drum__brakedrum__drum  a hollow cast-iron cylinder attached to the wheel that forms part of the brakes
  supertype:  #cylinder.round_shape  a surface generated by rotating a parallel line around a fixed line
  part of:  #drum_brake__drum_brakes  hydraulic brake in which friction is applied to the inside of a spinning drum by the brake shoe

No statement uses or specializes #brake_drum; click here to add one.