The compression classes of socks

Depending on the degree of maximum compression exerted (at the heel), you can subdivide socks into compression classes. The international reference standard RAL GZ 387 provides the following subdivision:

Classes Type of compression Compression exerted on the ankle
CLASS 1 Lightweight 18-21 mmHg
CLASS 2 Moderate 23-32 mmHg
CLASS 3 Strong 34-46 mmHg
CLASS 4 Extra strong 49 mmHg e sup.