Product information updated on 2021-10-06, Manufactured by SBX Parts - Part Number 4HIGHGM03, 2003-06 Chev and GMC Wiring harness to convert headlights to 4 high operation, Positive trigger headlight system. Works with or without HID conversion. If soldering is not your strong point then grab one of these plug and play 4 high wiring harnesses so that when you turn your high beam headlights on your low beams will also stay on., A 4 high headlight conversion kit will keep your low beam headlights on when you switch to high beam. This does two things. First, it provides more light on the road and close in front of you when on high beams. Second, it provides instant light in front of you when switching back to low beams. This is very useful on vehicles with HID headlights as they can take a second or two to come to full brightness when first turned on.