Passive Metal Detector - Magnets

The order for 2 X Strong Block Bar Strip Cuboid Magnets Rare Earth Neodymium 100 x 10 x 5mm N42...has arrived.This will be Version 2.0 of my speaker magnet metal detector (see post link below for Version 1.0) and will look like a golf putter - lol

They are so strong I CAN NOT directly pull them apart when parked in their keeper. Have to twist/slide at one end the open them like a compass to pull apart.

The black thing on top of the plastic is the keeper. End to end I will get a 200mm sweep to cover more ground over the speaker magnet detector.