|The large sacks of parcels are opened.
The parcels are tipped out on to long tables.
Each parcel must be marked by a Post Office worker.
The worker uses a large rubber stamp to mark the parcels.
The rubber stamp prints the name of the Post Office and the date in a circle on the top of each parcel.
It also prints black wavy lines across the postage stamps.
These postage stamps cannot be used again.