About: http://webisa.webdatacommons.org/181532198

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	Preferably, the shell, the cover, and the valve including the stem are molded from a polymeric material, such as polypropylene, and are assembled to provide the closure.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com