A: These are driving regulations based on your location. Most countries around the world have adopted one set of standards or the other, and for headlights to be street legal they must meet and be marked with the regulations adopted by that country.
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IP Ratings
What is IP Rating? Learn About Ingress Protection Ratings
The Ingress Protection (IP) Code outlines a system of classification for the protection of electrical enclosures against the intrusion of foreign bodies...