My thermos flask worked fine for a few months until it suddenly stopped keeping the heat in entirely. How do vacuum flasks stop working? - Quora
![Amazon.com: Mira 10 oz Insulated Small Thermos Flask | Kids Vacuum Insulated Water Bottle | Leak Proof & Spill Proof | Taffy Pink: Home & Kitchen Amazon.com: Mira 10 oz Insulated Small Thermos Flask | Kids Vacuum Insulated Water Bottle | Leak Proof & Spill Proof | Taffy Pink: Home & Kitchen](https://m.media-amazon.com/images/I/51kX7BMVl4L._AC_SY350_.jpg)
Amazon.com: Mira 10 oz Insulated Small Thermos Flask | Kids Vacuum Insulated Water Bottle | Leak Proof & Spill Proof | Taffy Pink: Home & Kitchen
![The diagram opposite shows how a thermos flask works Summarise the information by selecting and reporting the main features and make comparisons where relevant You should write at least 150 words The diagram opposite shows how a thermos flask works Summarise the information by selecting and reporting the main features and make comparisons where relevant You should write at least 150 words](https://www.testbig.com/sites/default/files/styles/max_325x325/public/Thermos%20Flask.jpg?itok=NHg48BH6)