About: http://webisa.webdatacommons.org/65973833

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 head portion 10 is preferably made of a hard material, e.g. metal or a hard synthetic material such as plastic, PVC, delrin, or any other synthetic material.
http://www.w3.org/ns/prov#wasQuotedFrom	google.es