Named after the Hindu goddess Kali, the Kali's teeth bracelet is a form of chastity device for men, designed to cause the wearer pain when an erection occurs. The device typically consists of a lockable metal ring that has spikes on its inner surface and is secured around the shaft of the flaccid penis. When the penis begins to erect, the spikes press into its soft tissue. These spikes may be blunted to avoid permanent damage to the wearer's penis, although one common form of the bracelet uses staples for the spikes. The goal of the device is to cause the wearer discomfort significant enough in the case of a partial erection so as to deter a full erection and other forms of sexual pleasure.
To be effective for enforced chastity, the circumference of the ring must be small enough so that the wearer is unable to remove the device even while flaccid.