The Ultra-Violet Turret, usually shortened to UV Turret, is an extremely powerful ultra-violet light mounted on Franklin's Junker. It is the only weapon in-game that can kill Kryll. The turret is mounted on the back of the vehicle and is only used once in the campaign during the Act 2 chapter, Burnt Rubber.
To help protect the Stranded in Ephyra, an Ultra-Violet turret was added to Franklin's Junker, which was used if they had to travel in night. It is unknown where the turret was obtained, although it was probably looted from the COG, since Chap tells Marcus that the Junker could not power both the vehicle and turret at once.
When Marcus and Dom needed to travel at night, they had to use the Junker, since the way to Franklin's Outpost is too dark to safely get there. Fortunately, the Junker had an Ultra-Violet turret. Marcus both drove the Junker and used the turret to incinerate any Kryll that dared to attack them. They later arrived at Franklin's Outpost safely where they fended off a Locust attack.
While the Ultra-Violet turret is not seen after this point, an UV spotlight was used by Pvt. Augustus Cole on a King Raven, which was shone on General RAAM. While it did nothing to RAAM (apart from flinching him), it incinerated most of the Kryll surrounding him.
- The UV Turret bears a resemblance to the 'spotlight' used to move Dom across one of the unlit streets towards the end of the Act 2: Nightfall chapter, Lethal Dusk. This is perhaps an intentional re-use of the original 3D model.