Adjustable or fixed calibration these conduction type thermostats sense temperature through a thermally conductive base plate. All units have a control range of room temperature up to 545°F with tolerance of +/- 5% of the set temperature. Compatible in both AC and DC systems up to 1500 Watts Maximum (Watts = Volts x Amp) These thermostats should be mounted directly to a flat surface or a special bracket can be provided for side mount. The terminals are # 6-32 tapped rivets. Custom shaft heights available with or without control knob.