About: http://webisa.webdatacommons.org/215618256

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	Such a backing block is formed of semi-rigid material such as hard rubber or plastic and positionally maintained by mechanical fastening, such as by adhesion.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com