About: http://webisa.webdatacommons.org/366972003

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	An apparatus according to claim 16 wherein said filter is a mechanical filter formed from an extensible tube having a diaphragm at one end, the microphone at the other, and a stub in the middle.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com