About: http://webisa.webdatacommons.org/384032260

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	These extension tubes 40 and 41 are typically formed of a polymeric material such as silicone, and are long enough to receive a pair of conventional clamps 42 and 43 for opening and closing the respective tubes.
http://www.w3.org/ns/prov#wasQuotedFrom	google.co.uk