These beverage holders are made of stainless steel and have double walls for insulation. They can resist both heat and cold and are designed to hold cans and bottles. To use, unscrew the rubber top and insert your beverage. They can hold 12 oz cans, 16 oz cans, or 12 oz bottles. The holders are also powder coated and can be given as gifts for various occasions such as bachelor or bachelorette parties, weddings, bridesmaids, corporate events, birthdays, or party favors.