gravity5
+1y
The lines are 100 percent necessary, and I can bet bosch, and for that matter, hella and osram have spent many thousands of dollars designing the optical properties of their light housings...which is far more than any ebay child labour headlights that people buy....I have run the HELLA and the BOSCH H4 housings on numerous vehicles of mine, and they are far far better than a sealed beam lamp.