The Trine 5205 series of tri-volt transformers are used for electric strikes, bells, buzzers, chimes, and other low voltage devices. A complete line of UL listed step down transformers and easy to install, low voltage, 120AC primary for residential, commercial and industrial uses. Transformers will safely take themselves off line when they overheat. Transformers can be either base mounted or attached to standard knockouts on boxes or cabinets. All primary leads are pre stripped for quick connection.