Four Sizes of Blank battle map boards (painted a mottled grey), with the grids set up for
1. Square Gridded / Gridless Wargaming
2. 5ft Square Gridded D&D / Pathfinder
3. 1y Hex Gridded GURPS, and 1m Hex Gridded GURPS-close-enough.

Why 'Blank' Maps?
Convenient pre-set starting points.

Why These Sizes?
Infiity / Frostgrave / Mordheim / Necromunda / Star Wars Legion use them, and they seem like reasonable sizes to use for RPGs as well. A Pathfinder/GameMastery Flip-Mat is the same width as the Tiny map width-wise, and 25% longer length-wise. I may add that size to the set in the future.