McCally Tools JC-5309 Flexible Calibration Allen Wrench

The McCally Tools JC-5309 Flexible Calibration Allen Wrench is an adjustment component used for accessing and turning small calibration screws in control assemblies and similar equipment. Its bendable shaft allows use in tight or obstructed spaces where standard rigid tools cannot reach in HVAC systems. Commonly used during setup or adjustment of pneumatic and electronic control components, it is applied in residential and commercial heating and cooling systems. It supports fine mechanical adjustments of control mechanisms to ensure proper calibration, alignment, and smooth operational response during system configuration and maintenance.