What material are ACO gullies made from? October 15, 2019 10:19 Updated ACO stainless steel gullies are manufactured from grades 304 and 316 stainless steel and are fully pickle passivated. To view full product details please visit www.aco.co.uk Related articles Do they come in different sizes? Why do you coat the whole of your outlet? Do they have a foul air trap? What size pipe do they fit? Can I use Modular 125+ around a swimming pool or spa? Comments 0 comments Please sign in to leave a comment.