• A (line) — Middle finger length, from the base of the finger to the fingertip
• B (line) — Palm length, from the fingertip (tip of middle finger) to the base of the palm, measured in a single straight line
• C (line) — Thumb length, from the base of the thumb to the thumb tip
• D (around) — Hand circumference (around the palm, across the knuckles at the base of the fingers)
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