Klein Tools ET05 Digital Pocket Thermometer

Yes. The ET05 reads from -40 to 482 degrees F (-40 to 250 C), which covers supply and return air, duct temps, and register readings with plenty of headroom. Room temperature accuracy is +/- 2.7 F (+/- 1.5 C). The 3-inch stainless steel probe slips into a duct test port or register, and the Max/Min and Hold functions let you capture a reading in an awkward spot and read it once your hand is back out.

No. The ET05 is not a medical device and Klein states it is not intended for use on people or animals. It is a tool thermometer for air, surface and liquid work on the job. If you need body temperature, buy a medical thermometer instead.

The probe is 3 inches of stainless steel, with a protective sheath that doubles as a handle when the probe is swung out. Three inches gets you past a register face or into a test port, but it is not a long insertion probe, so for deep plenum or large-duct center-of-stream readings you want a longer-stemmed meter. Folded up, the whole tool is 6.5 inches long and 1.08 inches wide.

It runs on two LR44 button cells, the common coin-style alkaline batteries. Auto power off kicks in after 15 minutes, so a unit bumped on in a pouch or toolbox shuts itself down instead of draining. Worth keeping a spare pair of LR44s in the truck since they are not something most supply houses stock in a hurry.

That is what it is built for. The body measures 6.5 inches long, 1.08 inches wide and 0.94 inches high, weighs about 0.087 lbs, and has a pocket clip. It rides in a shirt pocket or pouch like a pen, which is the point for a tech who needs a quick temp check rather than a full meter setup.

For a field delta-T it is workable: room temperature accuracy is +/- 2.7 F (+/- 1.5 C). Take supply and return with the same instrument so any offset largely cancels in the difference. If you need tighter tolerance for commissioning or documented certification readings, step up to a calibrated instrument with a stated accuracy spec that meets your procedure.

Both. F and C are user selectable on the unit, so a crew working to metric drawings or a spec sheet in Celsius can switch without doing conversions. The display is digital and backlit, which matters in a dark mechanical room or a crawlspace.

Max/Min holds the highest and lowest temperatures seen during a reading session, so you can sweep a duct run or a panel and come back to the extremes. Average smooths a fluctuating reading, useful in moving air. Hold freezes the current value so you can pull the probe out of a tight spot and read it. All three, plus auto power off, are built into the ET05.

Klein Tools ET05 is the part number, and the model is sold as a single configuration, so there are no finish or range variants to pick between when you order.