The Happy Bird Deluxe Wild Bird Solar Sipper is ideal for keeping fresh, clean drinking water available to the wild birds in your backyard. Unlike a bird bath, the Solar Sipper covers the water, keeping dirt and debris out of the water while allowing birds to drink easily from the 1.5 inch diameter opening. The outer shell insulates the water so it stays cool in the summer and warm in the winter. Its unique solar design defends it against winter ice to temperatures of 20 degrees Fahrenheit. Simply fill the Solar Sipper with clean water and place it in the summer shade or the winter sun. This is the perfect watering station for your backyard birds. Happy Bird's Deluxe Wild Bird Solar Sipper has a 7 inch diameter basin and holds 1 quart of water.