In the world of parcel post – as in other areas of human activity – size is critical.
But just when consumers may have got used to the new size criteria introduced by Royal Mail in April 2013, shapes and prices are about to change.
Two old types of "small" are out, and a "new small" will be introduced from 20 October.
Prices for the old "larger small" will be temporarily reduced – until 18 January 2015.
And the complexities get worse.