3 pcs black o rings for big co2 tank end, 3 clear gaskets on sodastream cylinder end, 3 pcs small o rings for bleed screw How it works:1.Cool the Soda Stream Cylinder in the freezer for 1 hour.2.Adjust the pin valve rod to a suitable position. (If you choose not to use in valve rod, you can skip this step.) 3.Screw the adapter to a commercial CO2 gas cylinder 4.The empty CO2 cylinder is screwed into the adapter5. For most big cylinders: turn the big cylinder upside down. (if you can not refill when the CO2 tank standing,because some of tank have not the dip/syphon tube inside.6.Carefully Open the valve of the large gas bottleThe valve on the Soda Stream Cylinder closes the flow if it is opened to much. This will happen if you open the big cylinder too much / too fast. The trick is to open de big cylinder very carefully. You will hear the air flow. So to fill it successfull7.After about 15-20 sec., The cylinder is completely filled8.Close valve of the large gas bottle9.Opening the bleed screw to drain residue remaining gas10.Unscrew the CO2 cartridge done When shopping, please pay attention to the size and dimensions of the product to ensure that it meets your needs. In the title and , we have provided detailed information about the product, including its features and specifications We want you to be completely satisfied with your purchase, so if you have any questions or concerns, please don't hesitate to contact us. We are here to help and will do our best to assist you. Thank you for choosing our product. We hope you enjoy it