Rule 1 governs the procedure in all civil actions and proceedings in the United States district courts, aiming to secure the just, speedy, and inexpensive determination of every action and proceeding. In the context of GD&T (Geometric Dimensioning and Tolerancing), Rule 1, also known as the Envelope principle, states that the form of a regular feature of size is controlled by its “limits of size". ^{cornell.edu 1 2 3}