E-Z Tiles is a series of 2-D terrain tiles from Fat Dragon games.
From the publisher's website:
E-Z TILES offer you a set of deluxe 1" scale fantasy tiles to add a new dimension to your fantasy adventure game. Each tile is fully customizable with multiple content options. Just click the items on or off in the Adobe Acrobat Layers palette to create the exact tile you want. With thousands of possible combinations, E-Z TILES is the most versatile fantasy tile system you can buy.