Johnson Controls T-3610-1003 Series T-3610 Pneumatic Low Limit Controller, 18″ Rigid Stem Element with Duct Mounting Bracket

Amazon.com Price: $204.50 (as of 03/08/2021 08:56 PST- Details)

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Adjustable from 0 to 270°F (0 to 132°C) at 8 psig
Factory set point at 57°F (14°C) with each gradation on the dial representing 2°F (1.1°C)