No, they're not.
Refer: http://en.wikipedia.org/wiki/Automotive_lamp_types
Low beams - 9006 bulbs or HB4 bulbs High beams - 9005 bulbs or HB3 bulbs
Bulbs can be replaced you have to get bulbs type 9006 (hb4)
H4
H4.
H4
Pull it out loosen the four screw and you will see the bulb I beleive it is h4 bulbs
A '98 Fiesta uses H7 bulbs, which comprises both your dipped beam and your main beam.
The lenght of a H4 HID Bulb is about 4 cm from the tip of the bulb to the en of the bulb where it enters the docking plate
Karun Technology offer all kinds of HID bulbs such as single beam bulbs, high and low beam bulbs, one xenon and one halogen bulbs. The most popluar items maybe H1, H3, H4, H7,H8, H9, H10, H11, H13, 9004... H4-3 H13-3 9004-3, 9007-3.... However you also could choose LED lights which are the main application orientation
9006 HB4
The H in H4 when thinking about a lamp would mean a halogen headlamp. So when stocks people are looking for specific bulbs for their customers they should know to look in the car head lamp section of the store when asked for a bulb starting with the letter "H".
I have vintage headlights converted to h4 halogen bulbs, my 30 amp fuse blows when i hit high beam, i was told to install a relay, hoe do i do this??