Conker only wears the Helmet in the Clang's Lair portion of the Bats Tower chapter, which allows him to better navigate through the dark water. The headlamp is operated by a battery that quickly runs out. Conker can replace the battery by going to the nearest B Pad located above surface in parts of the area. Conker needs the helmet to see the paths illuminate, as he must follow a specific path to reach the Boiler Room.
In the ECTS 2000 build, Conker wears the Helmet in a test level of Clang's Lair. The Helmet inexplicably has blue spikes attached to it.
Conker was planned to wear a Helmet in the cavern area of Twelve Tales: Conker 64. The Helmet is metallic rather than yellow.