I have the Howard's Horns Dynamic Duo. They are loud and appear to be a quality product. They however are not plug and play. To install them correctly you need to build your own wiring harness and must install the supplied relay for correct operation to reach maximum output db.

 

that's true ,but they are loud and they look good .

 

A buddy of mine has these on his Heritage. I ordered the set for the Ultra (shorter trumpet due to the lowers) and they should be here Tues. Can't wait. The stock horn sucks. I put a train horn on my Avalanche and it definately gets attention. Gotta love a loud horn