The Bugaboo newborn inlay can only be used in a Bugaboo stroller in the pram body mode.
It is not possible to use the newborn inlay in the seat configuration, since it is not designed for use with the comfort harness. This makes this product not suitable for children older than 6 months.
You should never use the newborn inlay in combination with other non-approved products, such as car seats, seat liners, footmuffs, play yards, etc.