What is "pear of anguish"

n. choke pear

The pear of anguish, or choke pear is the modern name for a type of instrument displayed in some museums, consisting of a metal body (usually pear-shaped) divided into spoon-like segments that could be operated by turning a screw. The museum descriptions and some recent sources assert that the devices were used either as a gag, to prevent people from speaking, or internally as an instrument of torture, although these accounts have been disputed as implausible.