The bigger the cup, the better the insulation.

3000ml--4000ml keep warm for 30-36 hours

Note:

When testing, the environment is different, the climate is different, and there will be a little error. To measure the temperature, you need to fill the lid with 100 degrees of water and screw the lid until the water becomes warm. The test needs to be filled with 100 degrees of water for the test. If it is not filled or opened in the middle, the time to pour out the water will be relatively reduced.