Vacuum flasks now come in lots of different shapes and sizes. You can have your own personnel mug flask to keep your morning coffee or tea hot on the daily commute, with or without a sip hole. If you like to carry a hot lunch or dinner then the wide mouth flasks are ideal as they have a large opening and are easy to clean. Die hard thermos fans are probably best suited to the traditional travel flask range that comes in varying sizes and volumes. Their sleek and slender design allows them to easily slip in and out of your rucksack when a brew is required.