I have a King 3B silversonic 1985/6 vintage showing 'red rot' in the slide crook.

If I replace the crook is it worth looking at alternatives to the brass crook?

Thanks for any help.

I don’t see the white dots in the middles of the spots, but I’m not an expert in this area.

Either way I think the regular brass crook ( I think you can get them from Hickeys. A tech should be order from a catalog anyway ) would be the best replacement. It’s a good balance for the rest of the horn. If someone makes a copper crook that could be spicy

Is it under the lacquer, or has the lacquer flaked off? Polishing the brass is really the only way to truly know if it is red rot. Well that or seeing if you can make the brass collapse with finger pressure.

That IS the place where you find it most often though.

If anything, the 3B crook is the go-to replacement for *other* horns of the same size. If there's something you want to change about the horn you could possibly get one from a boutique like Shires or Edwards but it'll be fairly pricey and definitely an experiment! Michael Davis replaced... I want to say a Sterling Silver King 2B with a Shires, the MD model. There is a similar model, the MD+ which is more in line with a 3B. That crook might be worth considering if it is indeed different than their normal crooks and available, fwiw. I'd probably go with the King personally. That part isn't expensive.