I'm making a DnD thing

I'm making a thing and thought it was 'bout time to show every one and get some opinions. I call them Dnd tiles and they are meant to help DM's make maps for their players without having to constantly re-draw to scale maps. It also helps the players visualize the world you are crafting.
Each peg hole is an inch apart and represents the center of a 5 foot area, similar to that of the dry erase mats I'm using under the tiles. Each building piece is modulated to be either 15 feet or 5 feet.

You're adventurers have been exploring the town, dungeon or whatever scenario you've created for them.

Looks like the adventurers have reached the end of the map. Time to expand their map.

Simply remove the tiles furthest from the adventurers.

Remove all of the modulated building walls and enviornmental pieces.

Slide the empty tiles in front of the adventurers.

Slip the tiles into place to lock up with the rest of the map.

Build up the rest of the buildings and environment with the modulated buildings

Continue play.
In just a minute or two you can expand your map with very limited disturbances to the flow of your game. Your players can help too by moving the tiles and placing the walls where you need them, making the expansion of the map even faster.

This is just a prototype, I still have plenty of work to do. However, I plan on 3D printing or making plastic molds of the final version sell them to interested people.

Hope you like em