"Headlights" for boat

I live in Decatur, AL and almost every boat I see on the water or at the ramp in north Alabama has a light attached to each side at the very front of the boat. Where do you find these lights? Are they a special kind or are they the ones at the auto part stores? I would like to get some before night fishing starts in the spring.

I have some I picked up at the local auto parts house.I use them for duck hunting,work good for setting decs out.