【Double-walled cup & heat insulation】Special double-walled cup design is better thermally insulated than single-walled water cups and lighter than ordinary thermos cups. The special double-walled cup wall structure effectively slows down the temperature loss of the drink in the cup, suitable for hot water, juice, cocktails, frozen drinks, and can be used repeatedly for a long time. 【Stackable design & easy storage】1 pack contains four cups, which can be stacked on top of each other, allowing one cup to fit into another cup, saving space and easily placed in any cupboard and drawer. Very portable, perfect for travel, camping, beach and picnic. 【A better alternative to glass and plastic cups】Instead of fragile glass, our stainless steel cup will not break if/when it falls on the ground. Unlike plastic, which tends to smell, these relatively light and handy cups retain the original taste of the drink. The cup is polished inside and outside, and the surface is smooth. The cups are made of