In its simplest form, a harness can be made from a length of rope or a nylon webbing tied round the waist. However this is extremely uncomfortable unless the wearer is very light. It can also ride up to the abdomen or even the diaphragm under load and cause serious injury. Looping the rope between the legs will prevent this, though care should be taken to avoid sensitive areas. More sophisticated harnesses exist in many patterns, designed to give greater comfort and security, and more options for carrying equipment.