MPC Truck Air Horns Super Loud Dual Horn Fits Behind Grille Overall Dimensions: 14.5"L x 7"W x 3.75"H Trumpet Lengths: 14.5" & 12" Trumpets Bell Width: 3.75" DB output: 149.7 db Construction: Chrome plated zinc alloy. **PLEASE NOTE: This horn requires a compressor and air tank to operate. The compressor and tank are not included in this listing. For a complete packages that include a compressor and tank, please visit other Amazon listings**