Beer Bottles are glass, not metal simply because beer tastes best out of a glass. The problem comes when we want to drink our kraft beer at a BBQ or a pool party. Metal pint cups or growlers give the beer a metal taste but glass at a party yea, not really. Comes along our Beer Glass and Sleeve it's lightweight, it's double-walled insulated, and it secures your pub glass. Constructed with a novel, innovative world wide pending patent technology that will keep your beer ice cold with no sweat on the outer wall.