I've got one myself. For only a bit more weight (~70g) than single-walled aluminum mug (~60g), Snow Peak can put two walls, making the mug insulated. Though it

I've got one myself. For only a bit more weight (~70g) than single-walled aluminum mug (~60g), Snow Peak can put two walls, making the mug insulated. Though it's heavier than an insulated plastic mug, and _way_ more expensive.