Core Sector Modular for Murder Squad tabletop game

I got sick of measuring out the play space for tabletop games, so I threw together this modular system to make it easy and (mostly) dummy proof. The tiles are each 140mm x 190mm which just happens to work out to 22" x 30" when you arrange them in a 4x4 grid. I've included two different versions, one for 3 x 1mm magnets and one for 5 x 1mm. Be sure of the polarity before you let the glue set!

This is a pretty bare bones quick and dirty system, so please feel free to remix with whatever terrai