The added advantage of this soda stream adapter is that you can use the side thumbscrew to depress the pin in the middle of the adaptor.  This pin adjustment makes the sodastream cylinder adaptor significantly easier to use.

This adaptor is used if you have a SodaStream Cylinder and wish to use a conventional Type 30 Regulator with it, perhaps for bbq or picnic and you don't want to carry your 6kg or 2.6kg Gas Cylinder this is the adaptor that will enable you to make a handy portable system.

Normal sodastream adaptors require an alan key to adjust the pin height and depending on how worn out your seal is you may need to adjust this pin periodically.  Also conventional cheaper sodastream adaptors also tend to leak gas every time you connect and disconnect them from your regulator or the adaptor itself.  This is also a pain. 

This new sodastream adaptor design is significant better designed with the handy thumb screw on the side of the unit allowing you to eliminate cumbersome adjustment and it also gives you the ability to turn off and on the gas flow.