Accessories that make Aerocovers work in your space. Cover Sandbags keep your cover in place no matter what the weather. PLEASE NOTE: Does not include sand. Our range of Aerocovers will provide resistance to water but they are not fully waterproof. If you are covering garden furniture, please do not leave your cushions under cover for prolonged periods of time. We do not recommend covering your furniture in warm weather conditions as this will affect the longevity of the fabric beneath the cover.