Ideal for tiring daily commutes, travelling and long-haul flights, as well as preventing extreme strain following long periods sitting, standing and walking, preventing the legs from swelling. Falke Ultra Energizing Travel and Comfort Strong Compression Socks are calf length socks designed to increase blood and oxygen supply, actively stimulating and supporting circulation with progressive, strong 18-21 mmHg leg compression. These breathable cotton blend compression socks have an anatomical left/right foot shaping and specially designed toe box with flat, smooth seams preventing rubbing or pressure in close-fitting shoes or when facing overlong days of walking. Licensed by Lufthansa for air travel.