Haers Double Wall Cold Insulated Water/Coffee Mug Cup - 500ml

 Steel Simple Modern insulated water bottles are made of high quality food grade 18/8 stainless steel metal. The mug is highly rust resistant and it will.
Vacuum Insulation Technology 
This bottle has a double-wall exterior with a vacuum seal between the walls. This means your drink temperature has no medium for the heat or cold to transfer through. Your drink will truly stay as cold as long as possible.  
Vacuum insulation provides superior heat retention--your beverage stays hot or cold for hours.Nonstick coated interior makes cleaning easy.
Recommended Tip for Maximum Beverage Enjoyment
In order to maximize the incredible insulation technology, it is recommended to either pre-chill or pre-heat the bottle just prior to use. This can be accomplished by filling the bottle with hot water, attaching the lid and letting it rest for a few minutes. Before you are ready to use, simply empty the water and fill with your favorite beverage. Attaching the lid will further increase the thermal efficiency.