2006 Cadillac SRX - Headlight Bulb Retainer

Headlight bulb retainers are a twist- or screw-on retainer that secures the headlight socket in the headlight assembly to prevent looseness that could allow vibration and prematurely damage the headlight bulb. These retainers are typically removed to access the headlight bulb, and must be reinstalled appropriately to ensure that the headlight assembly is properly sealed against moisture and that the bulb itself stays in place.