KA-BAR Original TDI Knife 2 15/16" blade length. Blade made with Aus 8A ss steel. Zytel handle. Your choice of either a straight or serrated edge. Comes with a hard plastic sheath. You can also have the option of purchasing Blaze Orange handled version of this knife with a straight edge.(See item 1480BO) In extreme close-quarter encounters where a suspect is attempting to take an officer's handgun, or an officer cannot access his handgun, the TDI knife is available as a "last option" knife. When worn on the pant belt the entire unit - knife and sheath - is well concealed. Designed by John Benner, founder and owner of Tactical Defense Institute.