Mobile Post Office No.3

An envelope with multiple single-ring "MOBILE POST OFFICE NO.3" cancels dated 27th July 1960, sent registered (with a Chard registration etiquette).  The postage was 3d plus 1/- for the minimum registration fee to cover £10 compensation.

According to a list available to download on the British Postmark Society website, Mobile Post Office No.3 was at the Chard & District Agricultural Show from 26th to 27th July 1960.