Green Capillary Mat - 18 x 18 Made of 100 percent UV-protected, non-woven polypropylene created from recycled plastic water bottles Capillary mats draw water upward using capillary action. It makes a great self-watering system for your indoor plants while you're on vacation. Capillary Mats can be cut to any shape or size to fit your individual gardening needs. Dimensions: 18" x 18" Listing is for 1 mat