These tile coasters are hand painted with acrylic paint and finished with 3 coats of high gloss polycrylic. The patterns are randomized as they were made using an acrylic pour and come in sets of 4 and measure 4x4. The bottom has been painted and rubber feet added to prevent scratches on your tables. Coasters are a wonderful way to add some creative design and color to your home, as well as protect your tabletops. Not dishwasher safe. To clean, just wipe with a lightly damp cloth. Do not hold under direct water. Keep in mind, these are ceramic tiles so they might crack or break if dropped. Because of additives added to the paint these coasters might have slight textures on the surface.