The UEi 550BN digital pocket thermometer with NIST calibration has a protective boot with a built-in magnet. The 550BN offers all the required features and ranges needed for today's HVAC applications including a water resistant ergonomic head for easy display readings. Housed in a hard case sleeve that also serves as a pocket clip, the stem can be slipped into the loop (built into the metal clip) to offer additional support or to insulate from the heat of the measured substance.