by Mike Goldstein
Kenneth Summers Lighthouse Image from Fotolia.com
Headlight bulbs come in different light sources and there are different models within each source. H1 and H4 bulbs are common types of halogen bulbs that differ primarily in their construction, use, and price.
The main difference between H1 and H4 bulbs is the number of filaments in each bulb. The H1 bulb is a halogen bulb, containing a single filament that uses 55 watts at 12 volts. The H4 bulb is a double filament halogen bulb that uses 60 or 55 watts at 12 volts, depending on the filament used.
H4 bulbs function as high and low beam headlights with a single reflector. They are the most used bulbs in motorcycles. H1 bulbs, on the other hand, require two bulbs for each headlamp, each with its own reflector.
H1 and H4 bulbs cost roughly the same price, from $ 3 to over $ 50. However, it takes two H1s to do the same job as a single H4.