If you really don't know it's a three piece assembly of steel tubing that, in the hands of someone who knows how to use it, can break bones and deliver a lethal blow to the skull. Used properly it can cause severe pain without inflicting serious damage.
If you are just being snarky I'd advise you to keep your attitude in check if you ever face an opponent armed with a "baton" as you won't like what happens next.
Regards,
GtG
I think people who think that way are supposed to be weeded out of the program during the first week.