For relieving tension from the torsion bar arm and key, allowing the user to safely to remove the torsion bar. For GM H.D. (8-Lug), 2WD/4WD, 1999-UP, For GM L.D. (6-Lug), 2WD/4WD, 1988-UP, For GM S-Series, Blazer & Jimmy w/Torsion Suspension, For Dodge 1500 w/Torsion SuspensionB14, For Ford F150 w/Torsion Suspension.