Valcomft. s 15-Watt Marine Horn is constructed in Non-Yellowing compound that is Perfect for shipboard and marinas and feature Easy Omni-Lock I-Beam Clamp Mounting System Weather- Interior or Exterior Resist Deteriorating Of Salt Sun High Humidity Equipped With O-Ring Seals Stainless Steel Hardware; Shipping Weight: 4.8 lbs (2.18 kg)Dimensions: 7.38in.