1. The bend specification for whether a non-round tube bend is “easy way” or “hard way”; more generally, the position of a tube’s cross-section relative to the plane of bend. This specification is commonly relevant to rectangular and oval tubing because it is necessary to identify whether the major (or long) axis of the tube’s shape is perpendicular to the plane of bend — i.e., easy way — or lies in it — i.e., hard way.
2. In a multiple-bend part, the location of the plane of one bend to that of another.