Stainless steel is a sturdy and durable metal, but it's a poor conductor of heat. Most non electric stainless steel food steamers have a 3 ply, 5 ply or 7 ply base with aluminum or copper core, where a few layers of metal bonded together to provide even heat distribution and make base thicker and more durable. The Buymee stainless steel vegetable steamer is fast and easy to use. In only minutes you can enjoy healthy, tasty vegetables, steamed to perfection.