The BladeForums.com 2024 Traditional Knife is ready to order! See this thread for details:
https://www.bladeforums.com/threads/bladeforums-2024-traditional-knife.2003187/
Price is $300 ea (shipped within CONUS). If you live outside the US, I will contact you after your order for extra shipping charges.
Order here: https://www.bladeforums.com/help/2024-traditional/ - Order as many as you like, we have plenty.
Butterfly knives are not legal in all states. But that level of legality varies. Some it is illegal to so much as own one in the privacy of your home (though it is largely unenforceable) while others like Maryland count them as normal pocket knives where they are legal to carry concealed.
Tennessee state law prohibits even mere ownership of "switchblades" but makes no mention of anything fitting the description of a butterfly knife. (Tenn. Code Ann. § 39-17-1302)
It is against the law to carry, concealed or openly, any knife with a blade longer than 4 inches. (Tenn. Code Ann. § 39-17-1307) Exceptions to this limit include "Incident to lawful hunting, trapping, fishing, camping, sport shooting or other lawful activity." (Tenn. Code Ann. § 39-17-1308)
It would seem they are legal to carry if they are under 4".
Source: http://www.lexisnexis.com/hottopics/tncode/
" “Switchblade knife” means any knife that has a blade which opens automatically by:
(A) Hand pressure applied to a button or other device in the handle; or
(B) Operation of gravity or inertia"
Key word is "automatically." In Taylor v. McManus 1986, the court ruled that this language excludes butterfly knives because their opening mechanism is not automatic (i.e. "self-acting") since they require the force of the hand and arm to open, not an integral spring that is under pressure and released.