A partially imagined obtuse triangle used for balancing the upper body during the setup.
leg #1: Imaginary line of connection from vital metacenter connector to the True Center (near the navel).
leg #2: Physical line of connection from True Center (near the navel) to the back of the left armpit (for people swinging down at the ball from right to left).
leg #3: The leading edge of the swing. The line of connection goes from the back side of the left armpit and down the underside of the left arm. It then terminates in the balanced connectors of the sublime metacenter.
see also conjunctive metacenter
see also vital metacenter
see also final metacenter
see also sublime metacenter
see also true center