This year, regulatory bodies introduced a new valve on standard propane bottles to avoid unnecessary gas flow when not connected to a device.
The new regulators to fit these, have been introduced to production, however we do still have some older style regulators available to ship.
If you receive an older style regulator, this will still connect to the newer style gas bottles.
If you receive the newer style regulator, this will require a newer style gas bottle.
For further explanation on this, please see this handy YouTube video - https://www.youtube.com/watch?v=RG1HxrqeNI8