Abstract: A self-locking lock nut assembly comprising working nut part (9) possessing a split annular sleeve extension upon which is mounted by springing locking part (10), which utilizes only the energy of vibration to translate counter-clockwise rotation of locking nut part (10) in a disengaging mode into a radial grip onto threaded bolt (6) through the split annular sleeve of working nut part (9) to prevent loosening counter-clockwise rotation of working nut part (9). The self-locking lock nut assembly possesses the capacity for a dynamic locking response to all modalities, directions and intensities of vibrational input to the degree required and proportional to the energy of vibration.

Abstract: A pencil eraser or erasable ink ball point pen eraser in the shape and form of a cowling sleeve affixed to the front end of either a double acting mechanical pencil or single acting ball point pen, wherein the writing elements of the pencil or pen may be withdrawn through spring action, making the eraser available for almost immediate application at the writing end of either instrument to erase whatever writing is to be erased, obviating the need for reversal of the ends of either writing instrument for access to an eraser at the non-writing end of these instruments.