Warranty
Both the M3 non-weather-resistant kit and the 127H weather-resistant kit are backed by a 2-year manufacturer's defect warranty.

Where space is a premium but compromising on the authentic train horn tone is not an option, meet the Mini Outlaw 3-liter horn kit. Expertly engineered to deliver the distinctive 3-chime metal train horn tone in a compact form, this kit proves that big sounds can come from small packages.
Powered by the M3 3-Liter air source unit, the Mini Outlaw guarantees a consistent, unmistakable tone, ensuring you're not just heard, but remembered. Designed for ease, this all-in-one kit ensures a seamless installation, transforming your vehicle's auditory signature in just a few hours.
(Note: Tank-mounted air compressors are not fully sealed. For this reason, we recommend the tank/compressor system be mounted in the upright position in an enclosed space away from moisture, dirt, debris, etc... Failure to mount this product as directed will void the warranty)
Detaching the compressor from the tank will void your warranty on this kit. If you need a solution where the compressor is detached, please look at our 232 and higher models.
One of our hottest new horns is now available in a weather-sealed entry-level kit! We took our iconic Outlaw horn, shrank it, and created a weather-sealed air system to go with it! This Mini Outlaw 127H kit is proof loud things come in small packages.
Detaching the compressor from the tank will void your warranty on this kit. If you need a solution where the compressor is detached, please look at our 232 and higher models.
A 3-chime metal train horn tuned for the deep, layered locomotive sound the Outlaw is known for, in a shell that fits where the full-size kit will not.
A complete onboard air source, compressor and tank both, in a footprint built for tight installs. It makes its own air and refills between honks.
The electric air valve comes pre-installed and the air source ships pre-assembled. Everything else needed for the install is in the box.
One recording of the Mini Outlaw 3-chime horn at full pressure. No editing.
Phone speakers undersell it. Earplugs ship in the box for a reason.
Same Mini Outlaw horn on both kits, weather resistant either way. The air system decides how long you can honk and whether the air source is sealed against the weather.

The M3 compressor and tank combo operates at 120 PSI, and the 3-liter tank provides 2 to 3 seconds of honk time. It refills from 90-120 PSI in about 35 seconds. The most affordable way to run the Mini Outlaw, backed by a 2-year warranty.

The 127H air source operates at 120 PSI, and the 1.5-gallon 4-port tank provides 4 to 5 seconds of honk time. It refills from 90-120 PSI in about 35 seconds. The air source is sealed against the elements, for builds that live outdoors.
The finish is the only difference. Same 3-chime horn, same air system, same roar.


Each kit ships complete and ready to install. The horn is the same; the air system and its plumbing are what change.
| Horn | Mini Outlaw train horn |
|---|---|
| Dimensions | 16.5″ L × 14.5″ W × 11″ H |
| Weight | 10.9 lb (4.95 kg) |
| Voltage | 12-Volt DC |
| Unit | M3 3-liter compressor and tank combo |
|---|---|
| Operating pressure | 120 PSI |
| Restart pressure | 90 PSI |
| Max amp draw | 18 A |
| Unit size | 16.535″ × 4.921″ × 7.086″ |
| Drain port | 1/8″ NPT |
| 0 to 120 PSI | 2 min (±10 sec) |
|---|---|
| 90 to 120 PSI | 35 sec (±5 sec) |
| Horn | Mini Outlaw train horn |
|---|---|
| Dimensions | 16.5″ L × 14.5″ W × 11″ H |
| Weight | 10.9 lb (4.95 kg) |
| Voltage | 12-Volt DC |
| Unit | HornBlasters 127H air source |
|---|---|
| Air tank | 1.5-gallon (6.6 L), 4-port |
| Compressor | 2L, 18 A max, 25% duty @ 100 PSI |
| Operating pressure | 120 PSI |
| Restart pressure | 90 PSI |
| Unit size | 15.2″ × 5.9″ × 12.8″, 13.75 lb |
| 0 to 120 PSI | 2 min 10 sec (±10 sec) |
|---|---|
| 90 to 120 PSI | 35 sec (±5 sec) |
Both the M3 non-weather-resistant kit and the 127H weather-resistant kit are backed by a 2-year manufacturer's defect warranty.
We offer a 30-day satisfaction replacement or refund guarantee on all purchases, except where otherwise noted in the product listing.
Merchandise may be returned within 30 days from the shipment arrival date for a refund. A Returned Merchandise Authorization (RMA) number is required for all returns, and a 15% restocking fee may apply. Please report any order discrepancy within 7 days of the invoice date.
Physical damage to any product voids warranty coverage. This includes improper handling and any damage sustained by irregular usage.
Tank-mounted air compressors are not fully sealed. Mount the tank and compressor upright in an enclosed space away from moisture, dirt, and debris. Failure to mount this product as directed, or detaching the compressor from the tank, voids the warranty. If you need a solution where the compressor is detached from the tank, look at our 232 and higher models.
This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.
These air horns are extremely loud. Wear hearing protection when testing at close range, never honk directly next to a person or inside an enclosed space, know your local regulations, and use the horns responsibly.
The Mini Outlaw Train Horn Kit ships complete, installs with hand tools, and packs the Outlaw tone into a footprint made for tight spaces.