The Kubaton (a registered trademark) is a plastic cylinder about 5 inches in length, and 3/4 inches in diameter, usually with a key ring at one end. It is not used for striking. It is a pain compliance device applied to a couple of pressure points. I beleive that Kubota will only back you in court if you are certified by someone who is a certified Kubaton instructor, and you are using an authentic Kubaton. This was stated in the manual I have, but it is pretty old, so this may have changed. The batonlight could also be used the same way as a Monadnock Persuader (same thing, different maker). Monadnock also has blocks and jabs with it. Close your fist around it and jab it into ribs, forearms, and a few other spots.
Also if you have a lot of keys on the ring, it can be an effective flail, used against the face. Neither Kubota, nor Monadnock teach this use however.
Almost forgot. Monadnock no longer seems to offer has the Persuader course as it's not listed on their web page. They still do make 4 versions of the Persuader though.
Also the Kubaton, and Kubaton type devices are IMO over-rated as self defense weapons for the private citizen. It's for the same reason as a wrist lock or other pain compliance hold. You want to get the person off, and away, from you, or stun them, long enough for you to escape. You're not trying to arrest them. For Law enforcement, and security they are pretty good. The Monadnock techniques are probably effective, but except for the Lethal Force Institute, I don't know of anyplace that still teaches it, and even the manual (Monadnock's) is no longer printed.