The Fieldpiece SPK1 Pocket-Size Digital Thermometer features a folding rod probe with a sharp tip for punching through flex duct and a stainless steel construction for increased durability. The probe rod folds away into the unit with no cover sleeve to lose. The compact sizing allows for storage within the user's pocket and can be hung from a vent or thermostat. 16 detent position grooves hold the rod at virtually at any angle or position. Offering a temperature range of -58 to 392 degrees Fahrenheit, the user can easily switch between both Fahrenheit and Celsius units for reading measurements.