(under the class definition) Subject matter wherein the free ends of the members, which constitute the joint interface, are so constructed that the particular configuration of one
requires a particular configuration in the other and/or the particular interfaces cooperate to produce some unexpected result.
SEE OR SEARCH THIS CLASS, SUBCLASS:
65+, for a duplicate end coupling (e.g., train line type).
148.19+, for diverse interfaces in serial diverse joints.
259, for a nonmetal-to-metal coupling having a particular surface means for increasing friction between the members.
