I am not a technician but could it be for the evaporator at the spring contact? Maybe they get the not 100% leak-proof, and if there Liquid durchrinnt then that's not sure the best for the contact of the fire button the yes directly below it. I myself have an SVD and Cool Fire 1 on both is a Kanger Aero tank top has the side air intakes, since no liquid can get to the contact of the battery carrier. My SVD and Cool Fire function properly for over 10 months.