Large varicose veins from 1 to 5mm are treated with a specially designed hand catheter. The catheter is manipulated with a sterilized handset. Scrolling the handset’s wheel will move the catheter into or out of the vein. These handsets are easy to hold and control, very flexible and the perfect insulation makes it possible to slide the catheter into a varicose vein and coagulate the vein from the inside. The catheter will be inserted into the vein and retracted step by step until the vein is completely closed. This thermocoagulation effect is similar to the treatment of the great saphenous vein.