A retractor includes a spool, a torsion bar and a torsion tube rotationally fixed to the spool, and a locking member aligned with the torsion bar. The torsion bar and the torsion tube extend coaxially from the spool to respective first ends, and the torsion bar has a key. The locking member is movable from an unlocked position rotationally disengaged with the torsion bar to a locked position wherein the key rotationally fixes the locking member to the first end of the torsion bar. When the locking member is in the unlocked position, the torsion bar may be plastically deformed to limit the load applied by webbing against an occupant. If sufficient force is applied to the webbing, the locking member moves to the locked position in which both torsion bar and the torsion tube are locked together and, in tandem, limit the load applied by the webbing.