Langbo 3156 Roof Bag, Chrome

AWESOME horns that DO NOT require a pressurized tank. I installed these high quality (Italian made), metal horns on my new 2018 GMC Denali Acadia, which has absolutely no room for an air tank of any size, let alone the larger "piston type" air pump required to pressurize such a tank.This kit uses TWO, fast acting, "rotary air pumps", that are each, slightly smaller than a Coke can. This makes them very easy to locate. On my 2018 Acadia (same model as a 2017), I mounted the two rotary pumps just behind the grill, inside the large OEM pocket provided directly under the hood at the front... right where the hood latch is (at the top, one on each side). I would have given this mAuto horn kit 5 stars if the kit was more complete with the required wiring and pre-attached female blade connectors. Not too much of a problem though... 12ga wire (minimum) and crimp-on female blade connectors are all available at any auto parts store.BUT... what made the installation MUCH SIMPLER was the replacement of the two included (cheap "chinesium") 30 amp relays (probably only 20 amps max each at that), with ONE, 100 amp automotive 12 volt relay from McMaster Carr (#7995K41 - High-Current Vehicle Relay, Water-Resistant, SPST-N/O, 12V DC). This relay is about the same size as the two included relays combined, but the "kit" now requires HALF the wiring as the two original relays would have required, and is a far more stout, American Made relay that will literally last the life of the car. I mounted this relay in the same "upper pocket area" on my Acadia, behind the grill, as are the two rotary pumps (keeps wiring short).As to the sound, I also own a GMC Duramax diesel truck that I installed the "tried and True", diesel air horns, with a 2-gallon air tank, heavy duty piston pump, pressure regulator switch (preset at 125psi), and the required air solenoid that is parallel wired with my OEM electric horns. Yes... it is LOUD, but these mAuto horns are not very far behind at all... about 90%+ as loud. Especially considering there is no pressurized air tank, with all the air line connectors that require maintenance every few months (some connectors require replacing because of multiple leaks, constantly bleeding down tank pressure). Since there is NO stored air pressure required with rotary pumps, there will be few if any leaks for the life of the installation (and NO high pressure connectors to constantly replace!!)What's also very cool, is that the "tone" of these mAuto horns is nearly identical to my 2018 GMC Acadia OEM electric horns, only MUCH LOUDER!!! There is a slight 1/2 second delay between the OEM electric horn activation and the mAuto rotary air pump activation, but there is also about a 1/4 second delay on my Duramax pressurized truck horns. This is because the rotary pumps require that 1/2 second to pressurize the two air lines (one per each pump & horn) before any sound is released. BUT, once released, boy howdy, is it LOUD!!!Actually, there is a very useful benefit of this 1/2 second delay. IF you are fast enough to just tap the horn quickly while driving, most of the time, only the OEM electric horns will sound off, and you won't scare the life out of a doddling pedestrian in a crosswalk... but hit the horn button hard, and you will blow that person right back up onto the sidewalk!!! My Durmax diesel pressurized air horns also have this same "safety feature", but they usually just squeak out an odd sound when tapped quickly. These mAuto horns won't do that (squeak)... if hit hard, you will get the FULL VOLUME of the air horns!! So, just a word to the wise... be careful around any cops!! A very cool setup indeed.....

Overall, nice loud horn...sounds like a semi/tractor trailer. If you have zero mechanical/electrical skills or knowledge you will have difficulty installing this but if you have intermediate or greater skills...no problem. The reason I am not giving 5 stars is I had to repair one of the compressors. I was halfway through the installation & then noticed the positive and negative terminal posts on one compressor was recessed all the way into the housing. I was about to return it but decided to see if I could repair it. I opened the housing, adjusted the posts (they weren't secured properly during manufacture) and inserted the motor back into the housing. (that was not easy aligning the magnets, coil, & drive shaft). After that I finished the installation and was very delighted by the loud, semi-truck sound now coming from my RV.

It's an okay horn, sounds more like a ship/boat horn to me. Not sure if it's any louder than the first air horn I had installed from a shop. It's still a very decent horn and I'd say it's worth buying if you're looking to change the tone of the horn in your vehicle. Overall, if you just want a horn with a more diesel sound, this is the horn. If you looking to do pranks, look elsewhere.

Really loud and worth the money! I put them on my F-150, painted the horns flat black, and hid them behind the grille. They do get people's attention 'cause I got the finger more than once......hahahaha.

Get ready for loud. Great quality, easy to install if you have a little sense of reading wiring diagrams. I'm not a techie but I figured out what the symbols meant on the diagram and when I installed mine it worked first time. It's not as low as a semi big rig but it's just as loud. I'm very happy that I installed this on my motor home.

If laud is what you want, well these will do , but nothing like a deep low train or semi sound, but better than others I had...

Loud as hell with just one pump. (comes with two). Tapped two lines into one. Hardest part was finding the room under the hood. It demands attention when you sound it off!

not really loud, but better then the1 in the car