About: http://webisa.webdatacommons.org/80595724

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	At least one set of the rollers can be raised and lowered to engage or disengage the underside of the panel, box, or other material being carried on the tables, depending on the desired direction of panel movement.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com