xenon upgrade

Hi.

I run a z650 - b1 - uk model(i think) - anyway - lighting is bordering on dangerous and i want to upgrade - it doesent seem to be a h4 bulb - it has no locating tabs - just a round base. any ideas what they call them h4, h3 ???
I dont want to waste time ordering a xenon that wont fit ?

Thanks guys

I bought a reflector that fit the headlight shell from Candlelight Inc. . they do have a flat face, but with a premium bulb work good.

Thanks John.
Checked out the site - very usefull stuff there - went with a 7" reflector - i can pick up any of the high output h4's locally when it arrives.

Thanks again