1The device is made by Manganese (Mn) steel alloy which mainly used to produce those professional electricity grid repairing equipment, so it is definitely strong and durable comparing with some other common iron materials (though still workable), this one is much stronger and not easily to distort even with high loading of body weight up to 440 lbs., For poles with different diameters, the product is very easily to adjust and match the target.2It's easy to hold your feet by the shoe safety buckles, and design has been dedicated with the anti-sliding design, including the "wing"shape protection wall by two side, very human and considerate.3Utility Field: electricity pole climbing, water pipe climbing, outdoor gaming or climbing contest, Team Building Program, etc. 4Kind Reminder: Please kindly be noted that this device can't be used independently without the security rope,then your hands would be liberated to handle your work,and this device is mainly use for low or medium height poles (like 20 meters or below).NOTE1. The size of the product is measured manually, and there will be an error of 2-3mm due to factors such as different measurement tools and measurement methods.2. This product is all taken in kind, but due to differences in photography, lighting, color deviation, and personal understanding of color. As a result, there may be some color difference between the actual product and the photo, and the color is subject to the actual product.3. Please take good care of our products~