Metal sheets + magnets seems like a good idea, is there something I should know? : r/ImperialAssaultTMG

Loving these magnetic cases! Case, magnetic rubber sheet and magnets all cheaply sourced online. : r/Warhammer40k

Super Strong Neodymium Bar Magnets 4 PCs

Pretty Little Magnet Boards - Organize and Decorate Everything

Buy Magnetic Sheet COMBO - Self-Adhesive online at Green Stuff World. Scale models, and board games

Magnetic Sheet pack for magnets - Self Adhesive

It is a bit more heavy than it looks and repels magnets. My neice found it and I would rather know what it is if she's planning to mess around with it.

Sheet Metal Magnets – Strong Hand Tools

Sheet Metal for Magnets

Magnetising Miniatures : r/InfinityTheGame

Complete paint job of Imperial Assault miniatures + some extras : r/ ImperialAssaultTMG