- The Trifecta measure three points—all from the hitter’s lead arm—during the swing. The measurements are from the shoulder, elbow and wrist.
- Measurement during the toe touch: lead arm should be at 130 degrees.
- Measurement during the heel strike: the measurement of the lead arm should increase about 10 to 15 degrees (140⁰ to 145⁰).
- Measurement during the slot position: lead arm should be an additional 10 to 15 degrees from the previous point (150⁰ to 160⁰).