An auto spinner banger is a standard bucket that has 2 or more holes in the sides. These holes are usually angled at 45° to cause spinning air currents inside the banger. Anything inside will be spun in the vortex air currents.
For the auto spinner banger to function properly, it needs a solid carb cap.. (i.e one that does not let air through.) Many different caps can fill the same job. A glass jar bottom will make do... even better is a solid marble that can sit right on top.