Chines, I was wondering about this very topic as well. I have a headlight to install that comes stock with both an H8 and an H11 bulb. Don't know if I can run those.
I am not an electrician, but I DID just read a wikipedia article on headlamps which included this bit:
"...[S]ingle-filament bulb designs include the H7 (55 W @ 12.0 V, 1500 lm Â±10% @ 13.2 V), H8 (35 W @ 12.0 V, 800 lm Â±15% @ 13.2 V), H9 (65 W @ 12.0 V, 2100 lm Â±10% @ 13.2 V), and H11 (55 W @ 12.0 V, 1350 lm Â±10% @ 13.2 V).
The first dual-filament halogen bulb (to produce a low and a high beam with only one bulb), the H4, was released in 1971. The U.S. prohibited halogen headlamps until 1978, when halogen sealed beams were released. To this day, the H4 is still not legal for automotive use in the United States. Instead, the Americans created their own very similar standard (HB2/9003). The primary differences are that the HB2 sets more strict requirements on filament positioning, and that the HB2 are required to meet the lower maximum output standards set forth by the United States government.
The first U.S. halogen headlamp bulb, introduced in 1983, was the 9004/HB1. It is a 12.8-volt, transverse dual-filament design that produces 700 lumens on low beam and 1200 lumens on high beam. The 9004 is rated for 65 watts (high beam) and 45 watts (low beam) at 12.8 volts. Other U.S. approved halogen bulbs include the 9005/HB3 (65 W, 12.8 V), 9006/HB4 (55 W, 12.8 V), and 9007/HB5 (65/55 watts, 12.8 V)."