I have a few of these sitting around, but have never actually had a use for them. I have one single hole yixing pot that is 40ml, and therefore too small for these to fit. I just ordered an 80ml single hole zini pot so I'm thinking I might use one of these filters on it and I'm wondering about a few things.
On the instructions (well the small picture on the plastic packaging) it seems that you just slide the two metal prongs into the spout from the inside of the pot. Is that all it takes? How well do these things hold in the spout, and are they prone to rusting? Do you take yours out in between uses? Do they scratch yixing?
For clarification, I'm talking about those small metal colanders with one metal rod bent through in a v shape. I searched the forums, but didn't find anything pertaining to these questions.