About: http://webisa.webdatacommons.org/309305751

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 stopper may be a compound or multicomponent formulation based on an elastomer, such as poly(isobutylene) or butyl rubber.
http://www.w3.org/ns/prov#wasQuotedFrom	google.co.uk