About: http://webisa.webdatacommons.org/334372803

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Each movable armature 18a, 18b is defined by a hollow open-ended cylinder made of a non-conducting, non-magnetic, material such as Delrin, sold by the E. I. duPont de Nemours and Company of Wilmington, Del.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com