Why use plain coasters, when you can customize our Clear Acrylic Plastic Set of 4 Napkin Holder Coasters? Simply slide any cocktail-size napkin in between the two layers of acrylic plastic - and go! The clear acrylic plastic coasters are 5 1/4 inches square; the clear acrylic coaster holder is 5 3/4 x 5 3/4 x 1 1/2 inches high. Please remove the protective plastic film from each coaster prior to use. Hand wash.