Icom IC-M304 Marine Base RadioIC M304 Waterproof Car Radio Station VHF Marine Radio Submersible Mobile Radio 25W For ICOMFeatures: Waterproof grade JIS 7, no water entering for 1m 3. 3ft and 30 minutes under water Large font display on the screen and 4 level adjustable backlight Channel collection function, which can quickly select common channels Automatic water removal function: send out vibration sound, which can shake out the accumulated water on the horn grid and make the