TR21-4 To W21.8-14 Soda Refill Adapter Cylinder Converter for Home Soda Maker

The CO2 cylinder only fits into the round side of the adaptor, and the sodastream cylinder must be placed into the hexagonal side. The sodastream cylinder filling adaptor is a product that enables users to fill their own CO2 from larger bulk cylinders into smaller sodastream cylinders.

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