The Humbler is a testicle bondage device.
Most often made of wood but sometimes of steel or even plastic it consists of two hinged sections. The bulk of the mechanism is two curved ends that fit snugly against the back of a man’s thighs. The scrotal sac is thrust through an aperture in the center. Ideally when the humbler is locked the man is unable to stand up because of the stress placed on his testicles.
The length of the scrotal sac may render this toy useless because the humbler will just hang loose.
Some people use two plastic clothes hangers of the right shape to create their own inexpensive DIY humbler.