The product is a set of vintage copper steam trap float balls. These float balls are used in steam systems to prevent water from entering the system and causing damage. Made of durable copper material, these vintage float balls are sturdy and reliable for use in various industrial applications. Perfect for businesses in the hydraulics, pneumatics, pumps & plumbing, or valves & manifolds industries, these vintage copper steam trap float balls offer a practical and efficient solution for maintaining steam systems. I believe they are copper - untested
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