Get something the size of a two or three D cell MagLight. It's a baton. It works. No one will question your having a big honking heavy MagLight. You can even get a rack type mount for a MagLight to mount it somewhere. edit: at one time I could find in Columbus code the limits on knives. I no longer can find it. It was something like 3.5 inch blade max. Bowie knives, of course, have special mention as deadly weapons in most city law. As far as I can remember, ASPs, numchucks, bullwhips, throwing stars, etc, are all considered weapons and at least subject to confiscation. http://www.sportsmansguide.com/net/cb/cb.aspx?a=359201 http://www.sportsmansguide.com/net/cb/cb.aspx?a=490355 http://www.cheaperthandirt.com/ZBB663-1.html http://www.cheaperthandirt.com/ZBB661-1.html http://www.cheaperthandirt.com/ZBB660-1.html I did see a sale for two not long ago. Two sizes.