Your flowers will look better than ever because this Self Watering Window Box - Green has two chambers. One for the soil and the other underneath which is a huge water reservoir that keeps the soil in the top chamber moist and plants healthy. The water reservoir has a 1.5 gallon reservoir. The soil automatically draws up the water from the reservoir as it dries up. Also, each planter comes with an easy to read water level indicator, which tells you when you need to water. So you only need to water once a week to enjoy fabulous flowers. Please note: brackets are sold separately.