Posted September 13, 2022Updated September 13, 2022Not ideal for d21 application.After tightened to specification, the safety pin installs well down the bolt, away from the bottom of the nut. My guess is that this keeps the nut from coming off, but doesn't keep the nut tightened to the spec in this application.ProsBall JointsConsMany PartsΒ 0Β 0Β 0