Kubaton Knife, for self defense?
A Kubaton knife is another form of the kubotans keychain. It usually comes in a hollow design that can be used as both a kubotan and a dagger knife when needed.
There are many forms of those in the market, but in most cases the knife is concealed in the hollow body of the kubaton. They are typically made of aluminum and weigh something between 2 and 3oz. In order to use the knife you will need to unscrew it and then fix the blade outwards.
We highly advise against using the kubabon knife for self defense. In our experience it doesn't qualify as an effective knife nor a kubotan due to its design and light weight which makes it ineffective as an impact weapon. It's also unpractical to use as a knife as in a real fight your attacker will not be patient enough to allow you to unscrew and fix the blade to use it against him and because of that it will surely get you into legal trouble if you are caught with it or had to use it in a real life situation. It's very hard to justify that this weapon is only used for defense and that you didn't intentionally want to harm your opponent.
There are some forms that is easier to deploy, but they might not be very secure to use as kubatons.
All in All, this might be a nice piece to own in your collection but definitely not an optimal self defense weapon.
Here is a quick youtube video, so you have a good feel of how kubaton knife looks like and used.
If you would like to pick one of those, you can buythe FURY Tactical SDK Self Defense Keychain with Internal Knife from Amazon for $4.49 below.