This Calor 11kg patio gas cylinder is designed for use with BBQs and patio heaters. It contains no gas and must be filled before use. The cylinder supports at least 20% renewable energy and should be stored outdoors. It is supplied empty, and an additional charge applies for gas refilling. If you already own a Calor 11kg patio gas cylinder, you only need to purchase a new one if you require an additional cylinder.