Drink Coasters - Set of 6. Fully Stackable. Made From Natural Bamboo Fiber. Protect Your Furniture From The Sweatiest Drinks. Great For Using & Gifting! Made from natural Bamboo Fiber. Finely ground Bamboo in its natural color is biodegradable and top shelf dishwasher safe. 3.75 inch diameter for glasses large or small. Unique design raises your glass above the collected condensation and prevents glasses from sticking to the coasters. Deep dish design holds up to an ounce of liquid keeping your furniture safe from the sweatiest drink glasses.