Theresa Berkley is credited with the invention of the 'Berkley Horse', a specially designed apparatus used for flagellation. This device became synonymous with her brothel and its unique services.

The 'Berkley Horse' was used to restrain clients in a specific position that facilitated flagellation. It likely allowed for more controlled and intense experiences, catering to the particular desires of her patrons.

While the 'Berkley Horse' is the most famous device associated with her, it is possible that she utilized other specialized equipment or implements to cater to the diverse interests of her clients. Descriptions of her brothel sometimes mention other instruments of torture.