Good morning. The Princeton Tec Surge runs on 8AA cells. Bulbs for that light are available from
brightguy.com.
Ok, the bulb seems to be a bi pin type. If necessary you can solder it into a PR base.
Not too sure if the Surge uses 8 cells, with two parallel rows of 4 cells in series,(6V) or if all 8 cells are in series (12V). Sorry for the added confusion.
EDIT: My bad... the bulb from the Surge runs off of 6V (4 cells) as stated in a review by
torchlightreview.com