This object is grandly called a 'Conformateur Allie Perfectionne'. It was used at hatter's T. Wells and Son, at 6 St. Andrew's Street, Norwich, to record customers' head measurements. When placed onto the head, the device moulds to the head's shape. Tiny pins under the lid pierce the outline of the wearer's head onto a piece of card. The card is then removed, and another device fitted around the outline made by the pin pricks, to ascertain the partiuclar size. This is then placed into a hat, which is adjusted by the hatter to make the perfect fit. One man was amazed on returning many years later to find they still had his head size for his school cap. It dates from the late to early 20th century.