Measure your midsection at the exact height where the belt will sit. Do not use your pants or standard clothing size.
If you do not have a flexible tailor’s tape, measure with string, then check the length with a tape measure.
Choose a size that places your waist measurement near the middle of the adjustment range. For example, 82 cm fits the Medium (70–92 cm) Strait Weight Belt better than the Small (60–82 cm) at its last hole.
