This is a new OEM Meyer Adapter Harness Kit 07185. This Adapter Harness is used with the Nite Saber Lights for a 1999-2002 Chevy and GMC with New Body Style. If your truck has DRL, you will need the Adapter Module Kit 07108 instead.
The Adapter Harness Kit is used with Headlight Bulbs No. HB4, HB3, H9006 and H9005.