I think that this is the only weapon that, when shot in the chest, will "knock down" an attacker. <img src="/images/graemlins/shocked.gif" alt="" />

http://www.fas.org/man/dod-101/sys/land/at4.htm

Very difficult to CCW, however. <img src="/images/graemlins/mad.gif" alt="" />

Also, I don't think TSA will allow it as carry-on. It probably needs to be checked, but I'm sure that someone else will know that for sure. <img src="/images/graemlins/grin.gif" alt="" />