The A419 series controls are single-stage, electronic temperature controls with a Single Pole, Double Throw output relay. They feature a lockable front-panel touchpad for setup and adjustment, and a Liquid Crystal Display (LCD) for viewing the temperature and status of other functions. A Light-Emitting Diode indicates the controls’ output relay (On/Off) status. The A419 controls are available in 24 VAC or 120/240 VAC models.