30–40 mmHg compression provides extra-firm graduated pressure for women with advanced compression needs. This level is commonly used under medical guidance for significant swelling, severe venous insufficiency, lymphedema management, chronic circulation concerns, and certain post-surgical or post-procedure recovery plans. Because 30–40 mmHg delivers a higher level of pressure, proper sizing is extremely important, and this compression level may be more difficult to put on than lower levels. For best results, it should be selected carefully and used with professional guidance when needed.