original "new old stock" vintage american industrial steam valve stem bonnet display stand salvaged from the boylston factory, chicago, il. the diminutive valve component would likely have been used in pressure regulators or pumps. the bonnet is comprised of cast iron with a brushed metal finish sealed with a clear coat lacquer. fabricated by the boylston steam specialties co., il. similar valve components available. measures 4 x 4 inches.