Adapter: H4 Male > H13 Female GMC The resistors get so hot

The resistors get so hot they can melt some light plastic and short wires

Designed to conquer compatibility concerns

lower profile for an easier installation

Legalize It: If you like green

If in the rare case something goes wrong

Adapter: H4 Male > H13 Female GMC The resistors get so hotUseful: Sometimes "this" just doesn't plug into "that" When the industry standard for aftermarket lighting calls for mostly 9006 Female inputs, these adapters will come in handy. Go Direct: If your vehicle's stock headlight circuit is strong enough to power ballasts without a relay harness, these are the perfect solution for non 9006 headlight systems since almost all HID ballasts require a 9006 female input. Standard: These are standard equipment on