(1) Every person who:
(a) Manufactures, sells, or disposes of or possesses any instrument or weapon of the kind usually known as slungshot, sand club, or metal knuckles, or spring blade knife;
(b) Furtively carries with intent to conceal any dagger, dirk, pistol, or other dangerous weapon; or
(c) Uses any contrivance or device for suppressing the noise of any firearm unless the suppressor is legally registered and possessed in accordance with federal law,
is guilty of a gross misdemeanor punishable under chapter 9A.20 RCW.
(2) "Spring blade knife" means any knife, including a prototype, model, or other sample, with a blade that is automatically released by a spring mechanism or other mechanical device, or any knife having a blade which opens, or falls, or is ejected into position by the force of gravity, or by an outward, downward, or centrifugal thrust or movement. A knife that contains a spring, detent, or other mechanism designed to create a bias toward closure of the blade and that requires physical exertion applied to the blade by hand, wrist, or arm to overcome the bias toward closure to assist in opening the knife is not a spring blade knife.