B&H Photo Video offers the 5.3-oz. Knog Qudos Action Waterproof Video Light for GoPro Hero
in Silver, model no. 11626, for $59.99
with free shipping
. (Eagle Camera via Amazon
charges about the same.) That's the lowest total price we could find by $33, excluding other Amazon sellers. It's waterproof up to 131 feet and features three Cree LEDs, a 70- to 400-lumen output, three light modes (with two brightness settings per mode), die cast and CNC machined aluminum heat sink, rechargeable LiPo battery with up to a 4.3-hour run-time per charge, and GoPro bracket.