About: http://webisa.webdatacommons.org/401883837

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 drilling tool of claim 20, further comprising an axial centering device including a pin projecting from said attachment end of said drill bit and insertable into a bore hole in said drill shaft.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com