Magnet holds 65 pounds on contact with 1/4" thick?? flat?? smooth ferrous plate in a vertical test?? 50% less on vertical surface holding against sliding force and less on steel with paint</br>Contains super powerful Neodymium?? Rare Earth magnet</br>Hook rotates 360 degrees and swings 180 degrees with opening beginning at 0.560"sing down to 0.350"</br>Includes non-scratch liner</br></br>Product Description</br></br><p>Ideal for holding and storing cables?? tools and wires. For outdoor applications shield magnet from water and humidity to prevent rust or search for ceramic magnet.</p></br><br/>http://www.amazon.com/gp/product/B00FN6PBQY..jp