Model HK9-Slimline: Universal "Demon™" Triple Steel Train Horns / Onboard Air System | 150 PSI | 3-Gallon PSI

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KL HK9-Slimline

Regular price $977.45
Sale price $977.45 Regular price $1,149.95

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PROP 65 WARNING:
This product can expose you to chemicals which are 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.

Model HK9-Slimline: Universal Onboard Air & Triple Train Horn 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" 730 HORNS?

  • 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 UNDISPUTED KING OF THE ROAD!

THE VERDICT: The undisputed crown jewel of the Kleinn lineup. If your goal is to clear the road with the earth-shaking rumble of a genuine 40,000-pound locomotive, the heavy-duty stainless steel 730 Demon™ Train Horn is your ultimate weapon of choice.

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 1/2" NPT heavy-duty brass air valve.
  • (Fitting) 1/2" Airline Connector: Compression fitting for high-flow air delivery.
  • Installation Hardware: Heavy-duty mounting bolts and high-strength fasteners.

BOOST YOUR BLAST: 30% MORE OUTPUT

Unleash the full fury of your Demon™ 730 Train Horns!

Experience the Demon™ 730 Horns in all their glory! The Ultra BlastMaster™ (6890) re-engineers your system’s architecture, maximizing airflow to deliver a devastating, high-decibel blast. It’s simple physics: more air equals more output. We ditched the standard 3/8” lines in favor of massive, dedicated 1/2” airlines leading to three High-Flow VX6003 brass solenoids—one for every individual horn.

This isn't just an upgrade; it’s a shocking twist on a classic, delivering soul-shaking locomotive blasts that command immediate attention. Overwhelm the senses and dominate the streets with the absolute peak of train horn intensity at your fingertip.

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.

Classic Chrome
  • Compact Air Horns: 102 / 130 / 141
  • Universal Air Horn Kits: HK2 / HK3 / HK4
Stealth Black
  • Compact Air Horns: 101 / 102-1 / 130-1 / 141-1
  • Universal Air Horn Kits: HK1 / HK2-1 / HK3-1 / HK4-1 / HKUTV

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.

Classic Chrome
  • Train Horns: 500 / 501 / 502 / 630
  • Kits: HK6 / HK8
Stealth Black
  • 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

Ultra Heavy-Duty Air Compressor
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

Slim Mount Air Tank
Part Number Model 6351RT
Warranty 1-Year
Tank Capacity 3-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 Five - 1/4" NPT Ports & One - 3/8" NPT Ports
Mounting Hardware Fitting Pack - 4 Bolts, Nuts, Washers
Max Pressure 200 PSI
Dimensions 27” L x 6” W x 8” H

AIR TANK FILL RATES

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.)
Model HK9-Slimline: Universal "Demon™" Triple Steel Train Horns / Onboard Air System | 150 PSI | 3-Gallon PSI

$977.45

Does it come with a warranty?

Kleinn Automotive Accessories Limited Warranty

Kleinn Automotive Accessories stands behind the quality and craftsmanship of our products. Our products are covered against defects in materials and workmanship when properly installed and used under normal operating conditions, subject to the terms below.

One-Year Limited Warranty

Unless otherwise specified, Kleinn Automotive Accessories products are covered by a 1-year limited warranty from the original date of purchase.

This warranty applies to the original purchaser and covers defects in materials and workmanship under normal use.

If a product is determined to have a covered warranty defect, Kleinn Automotive Accessories will, at its discretion, repair or replace the defective product or component.

What Is Not Covered

This warranty does not cover damage or failure resulting from:

  • Improper installation
  • Misuse, abuse, or improper operation
  • Use outside the product's intended application or specifications
  • Modification or alteration of the product
  • Accidents or physical damage
  • Electrical damage
  • Environmental damage or exposure
  • Normal wear and tear

Kleinn Automotive Accessories is not responsible for installation or removal charges, diagnostic fees, labor costs, vehicle downtime, loss of use, or other incidental or consequential expenses associated with warranty service.

Warranty Claims

To request warranty service, email warranty@kleinn.com with the following information:

  • A copy of your original sales receipt or proof of purchase
  • Your full name
  • Email address
  • Telephone number
  • A brief description of the issue

A Kleinn representative will review your claim and may first attempt to resolve the issue through technical support.

If the product needs to be returned for inspection, Kleinn will provide a Return Authorization (RA) number and return instructions. Products should not be returned without prior authorization.

Once received, the product will be inspected to determine whether the issue is covered under warranty. If a covered defect in materials or workmanship is confirmed, Kleinn will, at its discretion, repair or replace the defective product or component.

If inspection determines that the product does not have a covered warranty defect, the product may be returned to the customer, and the customer will be responsible for applicable return shipping costs.

This limited warranty gives you specific legal rights. You may also have other rights, which vary from state to state.

Kleinn Automotive Accessories
4045 N. Highway Drive, Tucson, AZ 85705
Tel (520) 579-1531

What's the returns policy?

How To Return An Item

Your item must be in its original unused condition to be returned, unless there is a manufacturer defect. You must return the item within 30 days of your purchase.

1. Please email support@kleinn.com to request a refund and we will assign you a Return Authorization #.

2. Mail your returned item to:
Kleinn Automotive Accessories
Returns Department
4045 N Highway Drive
Tucson, AZ 85705

3. Include in your package a signed letter stating the reason for your return and the original receipt.

Return Non-Exceptions

Merchandise that has been worn, used, or altered will not be accepted for return or exchange.

Restocking Fee

All returns are subject to a 15% restocking fee, which will be deducted from your refund. If shipping and handling fees were applied to your order, they are non-refundable.