aluminum cool cooling geometric grill metal radiator rectangles row rows rust rusty shape slit square texture textures vent angle angles appearance barbed-wire barbs barricade barrier caution cautionary-tape danger deteriorating double fence fencing gray grey light old plastic plastic-tape protect protection protective razor-wire restraint rusting secure security security-fence sharp silvery spirals strands tape twists warning wire aged collage grunge grungy paper papier series tattered tones torn variation variations worn abstract aging background brown concept creation decay design fill graphic green illustration image industrial mottled oxidisation oxidised paint peeling purple ruin rusted scrapbooking style ugly unique urban vector weathered blue violet corrugated black dark