ribbed metal surface

abstract aluminum architecture art backdrop background black blue bumpy clear concise construction convoluted design elevator floor grayish grey grunge hard heavy hilly hummocky industrial industry intricate iron just knobby laconically lumpy material metal metallic motley neat old ordinary panel pattern plate pockmarked precise ribbed rough sheet silver simple speckled spotted steel structure surface texture textured tough tricky tuberous uncluttered uneven wall wallpaper white