Stock photography, photos: ventilation pipe Stock photos of ventilation pipe Photograph: © Esa Hiltula Click for a larger image and more information Keywords associated with this stock photo: ventilation, pipe, vent, wall, bricks, blue, sky, white, clouds, background, outdoors, outside, exterior, architecture, building, chimney, day, daytime, roof, rooftop, grey, gray, aluminium, metal, metallic, vertical, design, air