The product is a thin foam rubber which does indeed easily accommodate bends or curves in the road (down to about 6 inch radius in my case)
Nice product. Very bendable, curvable, and follows (and smooths) easily over road contours. I used this and divided center line style on main roads. I used concrete style rolls (stones) for downtown streets. I used Smooth-It road kits for all secondary/rural roads. After allowing mixture to dry I painted it black and applied a very light texture of very fine black grandules on roads.