About: http://webisa.webdatacommons.org/375616868

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 head 64 can be formed of a suitable elastomeric material such as silicone and the valve stem 66 can be formed of a suitable magnetically attractive or magnetized material such as neodymium-iron-boron or samarium cobalt.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com