Piaa XTreme White Hybrid H4 Bulb Features: Piaa bulbs are engineered with Xtra Technology for greater performance per watt than any other bulb on the road Xtra is a term coined by Piaa to designate a high-efficiency bulb that is designed to produce greater light output than its rated power consumption (i.e. 55W 85W of light output). Claimed by Piaa The laws of physics still apply Greatly enhance your ability to see and be seen A metal bond holds the heat-resistant glass tube securely to prevent cracks and leaks A welded focus ring and one-piece filament support assures proper positioning