marine buoy lantern employs a heavily damped two - axis gimbal including an outer gimbal frame supported to the lantern housing by a pair of hinges and an inner gimbal member mounted to the outer gimbal frame by another pair of hinges . the hinges are made of plastic and respond very slowly to a torque applied thereto unlike gimbals employing bearings . the inner gimbal member supports the drum lens , flasher , lampchanger , and counterweights . the hinged gimbal cooperates with the counterweights immersed in a very viscous fluid to maintain the lantern vertically disposed notwithstanding angles of inclination of ± 9 °, or a total of 18 °, of the marine buoy mounting the lantern atop thereof .