About: http://webisa.webdatacommons.org/239880449

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	A tube is a circuit and each manufacture had their own metalurgy, coating, vaccuum, glass, skill standards.
http://www.w3.org/ns/prov#wasQuotedFrom	head-fi.org