Size 2 refers to a specific waist circumference in the manufacturer’s size chart, so the most important step is to measure yourself before ordering. Measure around the waist or the area where the belt will sit, keeping the tape level and not pulled tight. Compare that measurement with the LAUMA size chart rather than choosing based only on usual clothing size, because support belts need a more precise fit than ordinary garments.
When worn correctly, the belt should sit around the hips and lumbar region, covering the lower back without riding up or folding. It should feel firm enough to give support, but not so tight that it restricts breathing, causes numbness, creates sharp pressure points or makes sitting uncomfortable. The elastic knitted material is designed to stay soft against the skin, but fit and tension still matter.
The Velcro fastening allows you to adjust pressure for the situation. You may prefer a firmer setting during driving, gardening or careful lifting, and a looser setting when sitting at a desk. If the Velcro barely reaches, the belt gaps, or the support area does not stay over the lower back, the size is likely not correct even if the belt can technically be closed.