HO Sidewalks Made Easy The Bar Mills O Scale Sidewalk kit features parts made from a specially imported paper material that has the proper texture and thickness. The sidewalks come precolored in a dirty concrete color, are laser-cut to size and include laser-etched crack and curb lines. Sidewalk material is flexible, so applying them to your layout surface is easy even if there are grades or surface irregularities along the pavement′s edge.