Number eight

What's the postie meant to do here? Drop letters + parcels in behind the box?

[John Falconer]

?.? Well spotted though. Nice shot.

[Jon Lip]

Perhaps there's a secret door known only to posties?

[SandraD]

@johnfalconer + @jon_lip
Part of letterbox requirements is to avoid spring loaded mail flaps because it could cause injury to the postie. This example sorts that out!