This is a full-power railroad locomotive/ocean liner type compressed air horn squeezed into a bike-mountable package. Totally overkill, until you need to wake up some lethal driver. It’s got both the high and low ear-splitting tones of the individually sold Fiamm Freeway Blaster Horns, plus a little more oomph. The 139dB high and low tone blasters combine via air induction to cut through the din and make the most distracted of drivers drop their cell phones and pay attention. Installs easily on all bikes with a 4.5"×3"×4.5" space for mounting. The loudest motorcycle horn available. If Ethel Merman, Sam Kinison and John Philip Sousa ever had a band, and played through a wall-of-sound amp rack, it would sound like this. 12V. 1 lb 4 oz.