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Fun-Size Thermometer (RT345)

SKU: RT345

  • Tiny thermometer goes anywhere
  • Fits on a keychain
  • Fold-away probe design
  • °C/°F Switchable

Measure temperature everywhere you go! Friends and family will be amazed at your devotion to physical science! Just a tad slower and less accurate than our more serious, professional tools, you can't beat its convenience. The short penetration probe is blunted and folds away for pocket safety. Temperature affects virtually every aspect of daily life. Show the world how well you understand that! Get one for yourself and each of your buddies.

Has an accuracy of ±3°F. Switches between °C and °F. Includes keychain ring and battery. 30-day warranty. (Not designed for professional food safety.)

  • Range-58 to 248°F (-50 to 120°C)
    Accuracy±3°F (±1.6°C)
    Response Time15-20 seconds
    Auto-offAfter 10 minutes
    BatteryLR43 (1.5V) x 1 or equivalent (included)
    Probe1.42 L x 0.10 dia. inches (36 L x 2.6 dia. mm)
    Dimensions1.14 H x 2.68 W x 0.51 D inches (29 H x 68 W x 13 D mm)

    (Not designed for food safety. 30 day warranty)

Ratings & Reviews

4.6 / 5.0
7 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
Great Little Mini ME
Bought a couple of these as Gifts, ended up keeping one. Great for those times when you need a Thermo pen and don't want to carry the big guys. Hiking, camping, travel etc. Also a great conversation piece!
July 18, 2017

4 months ago
RT345 Keychain Thermometer
A very nice inexpensive way to have a handy and accurate thermometer with you at all times!
June 24, 2017

4 months ago
Another great Thermoworks product
Another quality product from ThermoWorks! I have this attached to my keychain and have found several uses during my daily activities. Recently went kayaking and some one asked what the water temp was, well there I was with this little handy device. As with my 4 other ThermoWorks products the quality is there and seems sturdy enough to keep up with the rigors of being on my keychain, plus it looks cool. I'm always interested in what you guys have coming out next, ok I'm admittedly a 65 year old gadget guy. Keep producing quality products!
July 2, 2017

4 months ago
Raving reviews
I purchased a bunch of these and sent them out as Farther's Days gifts to family and friends. I received great reviews and thanks. They all love fast digital readout.
July 3, 2017

4 months ago
Just One Problem
I really like my RT345. I bought it to spot check room temperatures around some equipment that must operate within a certain temperature range. The only problem I have is, I like to wear it around my neck on a lanyard and sometimes it accidentally gets bumped and turns on. I hope the battery doesn't die too soon. Love the small size for this use.
July 4, 2017

4 months ago
misplaced battery contact
We purchased five thermometers. At least one of them had a battery contact that was not extended. We had to use a dental pick to move it into the intended opening.
July 16, 2017

4 months ago
Response from ThermoWorks
We're sorry to hear that you had to fix the battery contact in this way. Thanks so much for letting us know that it happened so we can address this issue.
July 17, 2017
Rozanne PStaff
Fun size Thermometer
I wanted to thank Diane S. for what she did, Thank You so much. She sent me another Fun SizeTherm when I was having trouble with the one I had. Now I can go back to be your little PR person!! I've missed this! Everyone likes your products, I tell everyone all about you guy!! Thanks again! A customer for life!!
May 30, 2017