Blog

The GSI Microlite 500 Twist Vacuum Bottle is one of those items you might consider as a bit of a luxury, especially when going ultralight. Many will opt to carry a filter system over carrying liquid, so why do you need an insulated flask?

The first thing to note is that the Microlite Twist can keep liquid cold for 20 hours and hot for 10 hours, so is suitable for both winter and summer use. Its capacity is 500ml which for us is one large mug of coffee or two smaller cups. Not massive but certainly enough for most.

The 500ml capacity means that the design is nice and slim, yet it certainly feels robust and is nice to hold. The lid screws on and off easily with no leaks and provides a wide neck to drink from or pour out of. The base has a nifty rubber grip which further adds to its feeling of robustness and security. There’s also a strong plastic loop on the lid which comes in handy when moving it around. These design features combined make the  Microlite Twist a really nice wee bit of kit.

Our fist use was in winter Cairngorm conditions, including a particularly chilly spell of -12C for a low-level day walk. After 3 hours being stored on the outside side-pocket of a rucksack, the liquid inside was still steaming. A very welcome hot (but not scalding) coffee! Out of curiosity we also tried making a coffee in it just before bed, leaving it on the bedside table, and trying it first thing in the morning. At room temperature the coffee was still hot after approximately 8 hours. It would be fair to assume that on a summer day-hike, if you didn’t want to carry a stove for hot drinks, the Microlite Twist would be more than ample to keep a brew hot throughout the day.

Our next test was during a hot spell (28C) in June, when we carried cold liquid for a day at the beach. Obviously in hot conditions you will require more liquid than the Microlite Twist can hold, but never-the-less, it worked well and was a real treat having an icy cold drink when the liquid in our other bottles was lukewarm. We also amped up the chill factor by adding some ice-cubes which will have helped considering the bottle was in direct sun for at least 4 hours.

Our Verdict

While an insulated flask might not be a priority requirement for many, it really is great having an instantly hot or cold drink straight from your backpack. The insulation works well, and we found was ample for usual UK conditions (and even at the more extreme ends of our climate spectrum). While being small means you are limited to how much liquid you can keep hot or cold, it does mean it can be slim, compact and relatively light for easy storage in the side-pocket of a rucksack or for holding easily. We’ve used it for a range of situations – from the classic hot winter brew and cold summer drink – as well as hot chocolate for the kids and keeping berries icy cold. It’s something we’ve used in the great outdoors, on long car journeys and on family days out. 

Trek Scotland is a small family business based in the picturesque village of Tomintoul in the North East region of the Cairngorms National Park. They provide bespoke Mountain Guiding for Single Day Walks and Lightweight Multiday Trekking experiences, including wild camping, in the stunning Cairngorms wilderness and surrounding areas. Whether in the high mountains or lower valleys, their Multiday Treks are equipped with high quality, lightweight camping and trekking gear. They only work with small groups and, whatever your ability, pride themselves on designing your outdoor experience completely to your needs and with professional guidance and expertise. Adventure is waiting... Read more from Trek Scotland