Super Pet Flat Bac' Water Bottles www.petsmart.com - $4.99 (8oz. size) Product Description: The smooth flat surface fits tightly inside and outside your pet's home. Suction cups (sold separately) can be used for flat surface homes such as aquariums. Unique hanging snap lock bracket allows easy, fast refilling. Includes the one-of-a-kind "Friendly Floating Duck" refill reminder. RattyRat's Review: This product was awful. It leaked, was hard to clean, and hard to attach. We would not recommend these.