Steel carabiners - for the toughest applications
Steel carabiners may be very heavy, but they can also bear the most load. So they are often used as a braking carabiner for top rope climbing or for permanent use in climbing courses. Steel carabiners are characterized by an enormous resilience and provide breaking loads, which normal aluminum carabiner would not withstand. As they are extremely hard, steel carabiners are preferred in climbing and mountain schools or for clamping slacklines.
Steel carabiners are tough
Steel carabiners are much heavier than comparably sized models made of aluminum. But this also makes steel carabiners safer with the highest strength values and significantly better abrasion resistance. Steel carabiners demonstrate their strength especially with permanent longitudinal loads, but still have reserves for transverse and open loads where others carabiners quickly flounder. And if the hardened steel does buckle, then it doesn't break abruptly, but just slowly bends.