The iridescent finish of this Rainbow Shine Tumbler makes it gleam and shine in a variety of colors--it's a great match for any Prom theme color or school color! The 20 oz. double-wall vacuum insulated tumbler is made of stainless steel and a copper lining, and includes a press-in, twist closure lid. Customize one side of the 7 1/2" high x 3 1/2" diameter Tumbler with your one-color imprint. Add your school name and logo, Prom theme, Senior Party theme, motivational message, or any other design you wish! NOTE: Keeps beverages hot for 5 1/2 hours or cold for 24 hours.