WW1 City of Bristol Special Constable lapel / cap badge

A scarce original First World War period 'City of Bristol Special Constable badge'; large gilt blue enamel title surround 'City of Bristol Coat of Arms' to voided centre the reverse impressed with maker's details 'J.R.Gaunt London' and official number or date '1915'. Good condition, complete with original buttonhole fitting, no stress marks, minor red enamel loss to central shield,Diameter approx 34mm.