Gutter downspout covers are mesh or screen attachments placed over the opening of downspouts to prevent debris, such as leaves, twigs, and dirt, from clogging the downspout. They allow rainwater to pass through while blocking debris, which can cause blockages and water damage to the home and foundation. Downspout covers are typically made of durable materials like aluminum or plastic and come in various sizes and shapes to fit different downspout sizes.