Instrument - Brass Switch Physical description Short circuit and contact Brass switch Set of 3 Inscriptions & markings Inscribed with H W Sullivan Ltd London Item a Inscribed on base with No 5306 painted on base with 5222 Item b Inscribed on base with No 5304 Painted on base with 5223 Item c Inscribed on base with No 5274 Painten on base with 522c