The A11 Series low temperature cutout controls incorporate a 20-foot long, vapor charged, sensing element. The A11 reacts to the coldest 18-inch section of the controls sensing element. The A11 is suitable for monitoring the face temperature of hot water coils for freeze protection.Features: Snap-acting switch External temperature scale Easy setpoint adjustment with top or bottom access Product Specifications BRANDJohnson Controls BULB SIZE INCHES20' of 1/8" O.D. Tubing DIFFERENTIAL TEMPERATURE °F8 TEMPERATURE CONTROL RANGE °F35 to 45 SWITCH ACTIONSPST - Open Low LIMITED WARRANTY YEARS1