Do these use D2S or D2R bulbs?

D2S. They're bi-xenon, so the same bulb handles both low and high beam via internal shutter. You'll need D2S xenon bulbs—standard halogen won't work with projectors.

Will these bolt straight onto my existing headlight brackets?

Mounting method not specified in the product data—test-fit before committing to fastener placement. Bring them to the car, dry-fit them against your bracket, and confirm alignment before drilling or fastening.

Do I need a ballast and igniter kit?

Yes. These are xenon projectors—you'll need a D2S ballast and igniter for each side to power the bulbs. Headlights alone do not include electrical components.