This is a nice small self contained digital thermometer. It came with a plastic slip insulating the battery, so that it was not powered (no mention of this in the instruction sheet). Powered it up by removing the plastic, and was suprised to find it indicating 22 degrees in a room that is normally around 15. Got my calibrated spirit thermometer, and left them next to each other for a time to adjust to room temperature. There was typically 4 - 5 degrees centigrade difference between the two thermometers.
The instruction sheet says "Source of error: Please change the battery before complaining" it also says "No gaurantee if the instrument is handled or opened improperly". There are no handling/opening instructions ! I will try to add a photo of the instruction sheet which is about 3 inches square.
Giving it every chance to work, I changed the battery, now I feel justified in complaining. 10 pounds for the thermometer, 6 pounds for postage, and 4 pounds for a pack of new batteries, for a rather unexciting ornament. Now another 3 pounds to send it back for a refund.
To be fair, the advertisement doesn't suggest that it is accurate, but why would you want a thermometer that doesn't tell you the correct temperature ?
Of course it could be a one off, but the litte phrase in the instruction sheet seems to suggest maybe not.