The double-walled MUSIC STORE thermo mug is made of metal-look stainless steel on the outside and plastic on the inside. The screw cap with click opening and anti-slip function guarantees drip-free drinking.
I have 2 of these! One is absolutely not hermetic, the liquid flows easily out of the can so it's wet all around! The second is realy good what concern the waterproofing!! But...
Not at all good for keeping your beverage warm!!!
There's no sufficient insulation!