I see these advertised as Part # LY7341801 but none of the sellers nor Lyman give the two diameters of the expander plug.
There's a chart kicking around somewhere on this website that gives expander plug dimensions. I'd rather get the numbers from someone who owns this particular M-die and knows how to read a micrometer.
Thanks.
Edit: No need to waste ink in telling me about the NOE product. I have them and know their merits. Just interested now in the Lyman product.