retaining ring 118 is formed from or includes a resilient material whereby ring 118 expands from the compressed configuration to the relaxed configuration due to this resiliency retaining ring 118 further includes a fixed ring end 122 and a movable ring end 124 which become closer together in the compressed configuration fixed ring end 122 may be tethered or affixed within groove 114 by any known means including welding brazing or adhesive alternatively fixed end 122 may be have a larger dimension than a remainder of ring 118 whereby an interference fit is formed with groove 114 in another embodiment shown in fig5 a fixed ring end 122 may be formed with a hook mateable with a projection within groove 114 not shown in yet another embodiment retaining ring is machined from the material of fastener head 104 when fixed ring end 122 is affixed within groove 114 ring 118 may be compressed or relaxed by controlling a position of moveable ring end 124 in one embodiment of the disclosure ring 118 is placed within groove 114 and is squeezed or coiled inwards about fastener 104 into the compressed configuration by applying pressure to different portions of ring 118 in such configuration an engagement notch 126 may be aligned with access port 116 of fastener head 104 once aligned retaining pin 130 may be inserted through access port 116 and engagement notch 126 to thereby retain ring 118 in the compressed configuration the assembled fastener 100 ring 118 and pin 130 shown.