I've seen plugs that have a 1/4" plug that screws over the 3.5mm plug. It is on my Sony MDR7506 headphone, and on some cables I have.
However, I've looked in the Neutrik, Switchcraft, and Amphenol catalogs and can't find it.
Is this part available? Who makes it? Who sells it?
Thanks,
David
P.S.
Splitter cables (e.g. dual RCA to single TRS) often have a plastic cover over the split. What are these plastic covers called, who makes them, and where can you buy them?