Poly-Strike Kubuton Poly-Strike Kubuton- great to put the keys on and also use as a self-defense item. They are approx. 6 inches overall, 1/2" thick and have machined grooves for gripping texture. They are solid polymer and come with a 2 inch keyring. The guard can be slid from one side to the other or be removed completely. Styles may vary on these because we custom make them.