The fishing magnet is a single sided nickel coated neodymium magnet, with a stainless steel  eyebolt

It is thought magnet fishing was initially started by boaters using magnets to recover fallen keys from the water.

Although the name states ‘Fishing Magnet’ these magnets are used for many more applications than fishing

 

Even at its compact size of 25mm (which refers to the diameter of the magnet) , this one-sided magnet has a pull force of 20kg

The pull force will be influenced by many factors, including material type, thickness, flatness, friction levels etc.

 

The magnet vertical pull strength rating of 20kg is measured in laboratory conditions using a solid steel plate which is 10mm thick with the magnet placed in the centre of the plate and positioned horizontally on top. An instrument that measures force pulls the magnet steadily upwards at a constant pulling speed of 80mm per minute. The force in kilograms, at the point just prior to the magnet breaking away from the steel plate, is recorded and constitutes the magnet’s vertical pull strength rating.