Oliver did see this and I got a call from Mr Robinson at the factory. He had called the toilet manufacturing company explained what my problem was. The bolt is brass,but the washers and nut are plated. He was very concerned and asked if there was anything he could send me to repair. Let me say, I've never bought a product,had a complaint,and received an unsolicited call to resolve the problem before. Kudos to the Oliver team on this one. I'm heading to the marine store for stainless nut and washers. I wouldn't think of asking Oliver to send them to me. I bet they would.