Know Nuts November Hex Heavy A six sided nut. Also referred to heavier pattern version of a as Finished Nut. standard hex Nylon Insert Lock nut with nylon insert prevent backing off. Nylock. Jam reduced height. nylock Wing wings' for hand tightening. Cap domed top over the end fastener. Acorn nuts are high crown type cap nut, used appearance. Flange built in washer like flange. Tee designed be driven into wood create threaded hole. Square four Prevailing Torque non-reversible lock temperature applica- tions. K-Lock or Kep an attached free-spinning external tooth washer. Coupling long connect pieces rod other male fasteners. Slotted conjunction cotter pin on drilled shank fasteners loosening. Castle