REI insulated mug in cold weather. 14 oz Nalgene any other time. I like the Nalgene for shaking up powder mix items, like protein powder or hot choc. A 14 oz Nalgene takes up less space and fits in my bear can when I've eaten down the food a little. Easier to measure with too.
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"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki

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