Review on MHDMAG Double Sided Magnet Fishing Kit With Grappling Hooks And Gloves, 760Lbs Combined Strength Super Strong Retrieval Neodymium Magnets With 100FT Rope For River Magnetic Recovery Salvage Fishing by Joshua Jemison

The strength of the magnet is determined by how much metal it attaches to. It comes off a fridge door or metal paneling on a car fairly easy. However, I wasn't paying attention and was magnet fishing off and iron bridge. The bridge was nearly a foot thick in certain places. It got stuck on the way up. My friend and I had to basically jerk it with all our strength at the same time to come off. We're both 200+ pounds and were also using most of our bodyweight. Another one got stuck and we had to use a mini crowbar to get it off. Be careful not to use the magnet on thick metal.