This is no ordinary Humbler, because it won’t just force your slave on his knees, but if he still misbehaves you have several ways to punish his balls.
Put his balls through the separate ball stretcher and stretch them as far as he can take it. If he still won’t listen, let his balls feel the spiked plate and he is sure to learn his lesson!
Diameter ball opening: 37 mm
Width Humbler: 36 mm
Width Ball stretcher: 24 mm