About: http://webisa.webdatacommons.org/52800058

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	The valve seat body 43, the counterpart disk 46 and the spring plate 48 may be made of metal, a suitable plastic, or some other material, such as ceramic.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com