Not just any pillar-box...

This handsome Victorian red pillar-box is a listed construction, the smallest in Bournemouth

It is a Penfold hexagonal pillar-box, with the VR (Victoria Regina) marking seen on the front (Go Large to see it clearly)

Green was adopted as the standard colour for the early Victorian boxes. Between 1866 and 1879 the hexagonal Penfold (named after the designer John Penfold) became the standard design for pillar boxes and it was during this period that red was first adopted as the standard colour.