Its perfect for about an hour hike.

I put in my yoga side pockets during my workouts and it’s thin in shape and doest stretch my phone pockets out.

I can keep in my suit jacket while in a meeting and it’s not noticeable.

Great for the plane or skiing too!

Make sure lid is on tight.

I have used this previously when it leaked. So I am giving it another try. After two uses, no problems. But it is not labor free. You must really be attentive to the cap, ensuring that it is tight and always clean it in warm water afterward. As a long time cyclist I have used this and other methods regarding GU type supplements. I am not sure that just bringing along a small plastic bag to use for the discarded individually wrapped product is more of a chore than using this product. I continue to test this proposition.

The flask is awesome , instead of carrying multiple individual packs of GU. I can fill up the flask and use as needed. No more mess of having the sticky empty packs in my pocket during runs or pack during hikes.

Easy , no mess, portable way to carry GU