Any DIY Store that sells BBQ Gas, ie Woodies or B&Q,will take back old cylinders for return to the Supplier.Calor Gas were losing so many cylinders that they introduced a Tariff system, so every time someone buys a full cylinder without bringing back an empty they will be charged extra.The secret is bring back your empties when you go for a refill and save yourself money, especially now the BBQ season is here.