KA-BAR Knives TDI Pocket Strike, Fixed Blade, 3.188 Blade Length, 7.75 Overall Length, Matte Finish, Black, Plain Edge, Drop Point, AUS 8 Steel, Black Nylon/Fiberglass Handle, Nylon Pocket Sheath 2491 The TDI Pocket Strike was designed by John Benner of the Tactical Defense Institute (TDI) as a comfortable" convenient" and concealable fixed blade. The hard plastic sheath of the Pocket Strike rests inside of your pocket and clips to the outside of your pants. The ring loop makes it easy to find and quickly deploy the Pocket Strike.