The official Maclaren Universal Packaway footmuff...
This footmuff liner is designed to be in-keeping with the Maclaren range of buggies. Being universal it means that it can be used on any Maclaren pushchair, but it can also be used (generally speaking) with any other pushchair too, so it does not have to be Maclaren pushchair.
The idea is that because the footmuff is thinner than the usual one it should help the pushchair fold up better with the footmuff staying on and in place.
The muff part can be removed on warmer days to leave just the liner, which is another nice feature of this Maclaren Universal footmuff. It is available in the colours of Black or Scarlet.