The material and the lid are decisive for the insulation time of mugs.
The insulation time can vary greatly from one mug to the next. A thermal mug made of double-walled stainless steel with a tight seal can keep hot drinks warm for up to 6 hours and cold drinks cool for up to 12 hours.
But here too, it is important to consider what you need the mug for and how long the insulation period should be.
If you are only travelling a short distance, it is more important that the mug is easy to open. For this, the insulation time can be a little less long.