Model HK9: Universal ProBlaster "Demon" 730 Stainless Steel Triple Train Horn & 5-Gal. Onboard Air System
KL HK9FE
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Model HK9: Universal ProBlaster "Demon" Triple Stainless Steel Train Horn & Onboard Air System
The Undisputed King of the Road
When the situation demands more than just a loud horn, the Demon 730 stainless steel horns dominate the road! Delivering a sonic roar that cuts through sirens, heavy machinery, and chaotic traffic, these precision tuned steel horns are the ultimate train horn solution. Engineered to move massive volumes of air, the 730 provides the deep, earth-shaking rumble of an authentic 40,000-lb locomotive.
XCR 2.0™ Extreme Durability
Featuring our signature XCR 2.0™ salt-spray resistant coating, the Demon 730 thrives in the harshest environments. Whether faced with coastal salt air or off-road mud, these horns are built to maintain their professional-grade finish and startling output for the long haul. The stainless steel construction ensures that the internal components won't succumb to the corrosion that destroys lesser horns.
Modular Mounting Flexibility
While the Demon 730 comes mounted on a heavy-duty flat rack, it offers maximum installation flexibility. Each individual trumpet can be removed from the rack and mounted separately to accommodate even the tightest installation requirements on trucks, SUVs, or Jeeps. This modular architecture allows you to tuck the massive 6" to 7" bells into locations where a fixed-rack system simply won't fit.
WHY CHOOSE "THE DEMON" HK9?
- Unmatched Volume & Airflow: The undisputed crown jewel of the Kleinn lineup and our loudest stainless-steel triple train horn.
- Heavy-Duty Construction: Built with precision-tuned stainless steel trumpets for the most aggressive locomotive roar available.
- All-Weather Reliability: Signature XCR 2.0™ black coating provides extreme salt-spray and corrosion resistance.
- High-Flow Solenoid: Pre-fitted with a professional-grade VX6003 heavy-duty brass solenoid for instantaneous response.
- Modular Architecture: Detachable horns allow for custom mounting configurations tailored to your specific vehicle chassis.
THE VERDICT: Designed specifically for those who want to dominate the road, the 730 Demon™ is your weapon of choice. The Demon system delivers the ultimate raw power of locomotive excellence for your build.
Section 3: What's In The Box? HTML
WHAT'S IN THE BOX?
- (730) The Demon™ stainless steel triple train horns: Precision-tuned trumpets on a detachable flat rack.
- (VX6003) High performance air solenoid valve: Pre-installed 3/8" NPT heavy-duty brass air valve with 12' of 1/2" heavy-duty airline.
- (6450RC) Waterproof air compressor: 100% Duty Cycle — 200 PSI fully sealed unit engineered for harsh environments.
- (6450RT) 5-gallon air tank: Features an internal anti-corrosion coating for superior rust resistance.
- (INF-1) Tire inflator kit: 24’ heavy-duty air hose, tire inflator with luminescent gauge, and quick-connect coupler in a canvas storage bag.
- (2151) Pressure switch: Automated air management (110 PSI on / 150 PSI off).
- Installation essentials: Horn button, Juice-1 thread sealant, high strength airlines, and all hardware.
BOOST YOUR BLAST: 30% MORE OUTPUT
Unleash the full fury of the Demon™ 730 Horns!
Push the 730 Demon™ train horns to the edge of sanity with the Ultra BlastMaster™ (Model 6890). This upgrade adds two additional Model VX6003 high-flow solenoids and swaps the standard tubing for a massive 1/2" airline.
The result is bone-rattling decibel levels that demand respect across entire city blocks. Experience the 730 Demon in its most aggressive form—because "TOO LOUD" happens to be just right.
TOO LOUD? TOO BAD!
Air Horns vs. Train Horns
Find Your Signature Blast
The Screamer
Compact Air Horn Series
Engineered for "Emergency Vehicle" authority. This series delivers a sharp, high-frequency blast designed to cut through ambient noise instantly. With 3.5" bells, these horns produce a piercing scream that commands attention.
- Compact Air Horns: 102 / 130 / 141
- Universal Air Horn Kits: HK2 / HK3 / HK4
- Compact Air Horns: 101 / 102-1 / 130-1
- Kits: HK1 / HK2-1 / HK3-1 / HK4-1 / HKUTV / Vehicle Specific Kits: 102, 102-1
The Deep Rumble
Train Horn Series
Don’t just make noise—make an impact. Engineered with massive 6-7" bells, our Train Horns move huge volumes of air to create a deep, earth-shaking rumble. This is the authentic tone of a classic 40,000-lb locomotive.
- Train Horns: 500 / 501 / 502 / 630
- Kits: HK6 / HK8
- Train Horns: 220 / 230 / 730
- Kits: HK5 / HK7 / HK9 / HK9-Slimline
Professional-grade engineering. Legendary Kleinn Performance.
Train Horn Specifications
| Triple Steel Train Horns | |
|---|---|
| Part Number | Model (730) “The Demon" |
| Number of Horns | 3 (Flat Rack or Individual Mount) |
| Warranty | 2-Year Warranty |
| Construction | Stainless Steel Trumpets |
| Brass Solenoid | P/N VX6003 (12-Volt) |
| Max Pressure | 200 PSI |
| Output (dB) | 157.8 dB (159.6 dB w/ 6890 Upgrade Kit) |
| Rack Dimensions | 22.5” L x 18.5” W x 7.25” H |
| Trumpet Lengths | 21.75”, 17.75”, 13.5” |
| Airline Size | 1/2" OD Airline |
Air Compressor Specifications
| Feature | Feature Details |
|---|---|
| Part Number | Model 6450RC |
| Warranty | 2-Year Extended (6450RC, 6650RC, & 730) |
| Max Pressure | 200 PSI |
| Duty Cycle | 100% @ 100 PSI (@ 72° F) |
| Flow Rate | @ 0 PSI (13.8 Volts): 2.5 CFM |
| Compressor Type | Waterproof Sealed, Oil-less |
| Voltage | 12-Volt DC |
| Motor Type | Permanent Magnetic Motor |
| Max Tank Size | 7.0 Gallon |
| Max Amp Draw | 23 Amps |
| Dimensions | 11.25” L x 4” W x 6.50” H |
| Mounting Holes | 8.90” L x 3.31” W (5mm Diameter) |
| Mounting Note | Mountable in any position except upside down |
| Shipping Weight | 12 lbs |
| Pressure Switch | P/N 2151 (Works with 52175 Safety Valve) |
Air Tank Specifications
| 5-Gallon Air Tank | |
|---|---|
| Part Number | Model (6450RT) |
| Warranty | 1-Year |
| Tank Capacity | 5-Gallon |
| Construction | All Steel Design (Gloss Black Epoxy Finish) |
| Internal Coating | Cortec Internal Anti-Corrosion Coating |
| Mounting Legs | 2 Legs w/ 4 Mounting Points |
| Air Tank Ports | 6 - 1/4" NPT Ports & 1 - 1/2" NPT Ports |
| Mounting Hardware | Fitting Pack - 4 Bolts, Nuts, Washers |
| Max Pressure | 200 PSI |
| Dimensions | 19” L x 10” W x 13” H |
Air Tank Fill Rate Details
| Tank Capacity | Pressure Range | Fill Rate |
|---|---|---|
| 2.5 Gallon | 0 - 150 PSI | 2 Min. 54 Sec. (+/- 10 Sec.) |
| 2.5 Gallon | 110 - 150 PSI | 54 Sec. (+/- 5 Sec.) |
| 5 Gallon | 0 - 150 PSI | 5 Min. 57 Sec. (+/- 10 Sec.) |
| 5 Gallon | 110 - 150 PSI | 1 Min. 53 Sec. (+/- 5 Sec.) |
Installation Links:

$1,329.95