I'll go ahead and let AC Lighting Consultant Daniel Stern describe:
There is nothing such as an H5 headlight bulb. It is an imaginary designation. What is meant by the commonly used "H5"—used in US/Canada 911s starting in 1987—has (only) two designations: 9004 and HB1. The best such bulbs are ultra-high luminance items without_ any blue tint on the bulb glass. They're an uncatalogued item made by Osram-Sylvania, considerably better for intensity and beam focus than any of the parts store items.
Please do not use LED bulbs in reflector headlights like these bulbs are designed for. You may have noted that we do not sell individual LED headlight bulbs for that reason. If they worked properly we would sell them. Click here for the details on why they are a disaster from Daniel.