Zak Designs Triangle 13-Ounce Aqua Double-Old-Fashioned Glasses, Set of 4 Set of 4 plastic 13-ounce drink glasses Triangular base concentrates color for prismatic effect Made of strong styrene copolymer; substantially weighted to feel like glass Great for patio entertaining; matches other Triangle drinkware Dishwasher-safe in top rack; not for microwave use