I've got two, one is the normal sort with Mercury in it and you push a button to reset

http://www.brannan.co.uk/images/pl/12-403-3.jpg
Looks like this

The other was a bit more expensive and is a digital one with two sensors so I could monitor the outside & inside temps if I wanted to but as it's a large greenhouse I tend to monitor the temp at one end (above the heated bench) and in the middle of the house.

http://www.brannan.co.uk/images/pl/12-412-3.jpg
Looks like this
The first cost about £5 and the other was £20

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ntg

Never be afraid to try something new.
Remember that a lone amateur built the Ark.
A large group of professionals built the Titanic

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