Ahhhh, no.

H4 and H3 are insert bulb types. H4 more typically the bulbs fitted to everything in the commodore/falcon range etc from the VB/XD (maybe C previously) and H3 are usually spotlight insert bulbs.

What the original poster was referring to are sealed beams, which do not have bulbs fitted to them but are a single unit with an integral bulb (if the light blows the whole unit - lens and everything is replaced).

The 7 inch sealed beam should just be a three pin type (single headlight H series front end) which incorporates high and low beam in the unit.

The two pin 5 3/4 sealed beams with two pins are only a single filament type unit (usually high beam). If you find any with three pins it is for high/low beam/earth - it with have two filaments in it (outer HZ). No they are not the same but at a pinch can be made to work to get you home....

Regards,

Dave.