About: http://webisa.webdatacommons.org/297964897

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 grooves may be of square or rectangular cross-section or they may be of such a configuration that they are enlarged at their bottom, being for example in the form of a dovetail-shaped cross-section.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com