I’ve just been on a 4 hour train journey with an inconsiderable

I’ve just been on a 4 hour train journey with an inconsiderable s**t shouting into their phone most of the way and refusing to quieten down or be considerate to me and others – he was at the end of the carriage, I was in the middle wearing 34dBm earplugs to little effect.

I need something I can use on the odd occasion when this happens.

Would your J260B do this?

If not, have you got anything that would work over the length of a railway carriage?

Preferably something that would fit in a pocket and run off a standard battery AAA/ AA  / PP3 (or a rechargeable variant of the same. Not a proprietary built-in lithium polymer..