Weight of the Gas: The 12.5kg label specifies the safe, maximum recommended weight of the LPG inside the cylinder.Safe Capacity: By safety standards, a cylinder is usually filled to about 85% of its total water volume. This allows the liquid gas space to expand safely when exposed to varying temperatures.Total Weight (with cylinder): The total physical weight you carry will be higher. The empty weight of the metal or fiberglass container (known as the tare weight) will add another 2.5kg to 5kg depending on the manufacturer, which is embossed on the cylinder's neck ring.