The Torrosett 51 binary heat-cannon was a type of energy weapon. It was shiny with "strange alien contours", and slightly smaller than a cricket bat. The cannon produced a concentrated beam of heat which could cut cleanly through flesh and metal. The weapon was double-barrelled, and each half could be fired simultaneously or split off and used separately. The weapons came with a kind of factory seal that allowed a user to see whether the weapon had ever been previously fired, and also had a self-destruct feature.
Czisch's mother brought a Torrosett 51 binary heat-cannon with her to Earth, leaving it as a sort of bribe for whoever would adopt her abandoned baby. When Pam Feerce was chosen by Czisch as a host she used one of the guns to protect herself, killing several local drug dealers and anyone else who threatened her. The other gun was kept in her house. When Torchwood Three learned of the killings, Jack Harkness was able to get one of the guns. Later, after Czisch took back control of Pam, she used the self-destruct button of the heat-cannon to kill both of them. (PROSE: The Wrong Hands)