16 in which the projectile 18 is completely enclosed attached to the upper portion of the container 12 is a top closed ring 22 and similarly attached to the lower portion of the container is a bottom closed ring 24 when the upper and lower portions of the container 12 14 are fully engaged for example by tightening the threads 20 rings 22 and 24 are aligned coaxially and thereby create a bore 26 which passes through both rings 22 24 the fastener 10 which in fig1 is shown located in the bore 26 includes an upper body 28 and a lower body 30 attached to the lower body 30 is a first projection means which may consist of several individual locking tangs in fig1 two locking tangs 32 34 are shown projecting from the lower body 30 the first projection means may also consist of a single projection completely encircling the lower body 30 the function of the tangs 32 and 34 is to prevent the lower body 30 of the fastener 10 from moving in an upward direction through the bore 26 when the fastener 10 is moved in an upward direction relative to the container 16 in fig1 tangs 32 and 34 abut against the lower surface 36 of the bottom ring 24 thereby preventing further upward movement of the fastener 10 however in addition to preventing the fastener 10 from being pulled.