(under subclass 613) Apparatus in which the earth working element or the immediate supporting means therefor is formed of resilient material.
SEE OR SEARCH THIS CLASS, SUBCLASS:
389+, for spring-tooth implements with wheel substitutes.
624, for a spring-formed standard mounted on a rotating carrier.
627, for spring teeth mounted on a rotating carrier.
634+, for parallel, pivotally adjusted tooth bars which may have spring-formed elements mounted thereon. 707+, for single-spring earth working elements.
