This Bottle Snug available at Notcutts, helps keep your pets water cooler & reduces algae growth in summer by protecting from sunlight, as well as reducing the risk of it freezing in winter. Fits round or square bottles with a circumference of 15 to 25 cm. Key Features Reduces algae growth Helps keep water cool Reduces risk of freezing in winter Fits round or square bottle with a circumference of 15-25cm