Features Grade 8A Ceramic Magnets High-Power Pole Configuration Thick Pole Shoes for Maximum Holding Power 3 Sizes/Strengths to Fit Many Applications From 150  to  500 lbs. Holding Power  Custom Sizing Available

Retrieving Magnets  - Designed for heavy-duty and underwater use, these high-power retrieving magnets will recover lost equipment, keys, tools, fishing tackle or any ferrous metal objects that may fall into deep water, wells or holes.   To remove captured objects, simply twist and pull object from magnet.

By making contact at the two pole shoes, the larger objects are prevented from  falling off during underwater retrieval.

As seen in this picture, the objects are  securely held at 2 points,  horizontally across the magnet's pole shoes.