Thermal mug matt black is a brilliant highly versatile mug which will keep your drink hot for up to 4 hours this mug is very useful and can be used in many places such as holiday artic golf course or mountains the mug is watertight so it can be put into your rucksack and it will not leak the thermal mug can also be used for cold drinks and this will keep your liquid cool for up to 12 hours comes with an expansion chamber with pressure release value in the lid capacity 300ml dimens