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LABOR DAY SALE • 15% OFF SITEWIDE • PRICES AS MARKED
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LABOR DAY SALE • 15% OFF SITEWIDE • PRICES AS MARKED
KL HK4
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STOP BEING IGNORED. START BEING HEARD.
The Model HK4 is engineered specifically for drivers who demand maximum sonic impact and a sharp, classic Chrome aesthetic. This system takes our best-selling platform to the next level by utilizing a quad-trumpet configuration to produce an even louder, richer, and more complex tone than standard setups. With four tuned trumpets, the HK4 ensures you have the undeniable presence of a much larger vehicle, making it the ultimate professional-grade upgrade to replace a weak factory chirp with a head-spinning blast.
PROFESSIONAL-GRADE PERFORMANCE
At the heart of the system is a high-efficiency 130 PSI air compressor paired with a 1-gallon air tank. This rugged, oil-less system is designed for durability and "set it and forget it" reliability. Featuring integrated thermal protection and a complete wiring and installation kit, the HK4 offers a dependable solution for drivers who require consistent, high-pressure performance on demand. Whether you are navigating dense traffic or open highways, this system provides the air capacity needed to power through any situation.
BIG SOUND – SMALL FOOTPRINT
Installation is simple thanks to the kit’s clever, low-profile design. Despite featuring four distinct chrome trumpets, the compact footprint of the chrome-plated metal horns allows for a seamless fit in tight locations—such as behind the grille or tucked neatly inside the engine bay—where traditional train horns simply won't fit. By choosing the HK4, you are joining thousands of drivers who trust Kleinn Automotive Accessories for superior quality and "get out of the way" authority. Don’t settle for a vulnerable factory horn when you can have the quad-trumpet power of the Universal ProBlaster™ HK4.
THE VERDICT: The Model HK4 is the ultimate premium multi-trumpet chrome choice for truck, SUV, and Jeep builds that require extreme dual-tone volume but need to fit into restrictive real estate footprint spaces.
The Screamer
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 in heavy traffic.
The Deep Rumble
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.
Professional-grade engineering. Legendary Kleinn Performance.
Too Loud? Too Bad!
AIR HORN SPECIFICATIONS
| Quad Chrome Air Horns | |
|---|---|
| Part Number | Model 141 |
| Number of Horns | 4 Horns (Single Mount) |
| Warranty | 1-Year Warranty |
| Construction | Chrome-Plated Stainless Steel |
| Vortex 4 Chrome 12v Solenoid | P/N- 307 w/ ¼” Airline Input |
| Min / Max Pressure | 120 - 150 PSI |
| Output (dB) @ 150 PSI | 150.3 dB |
| Dimensions | 14” L x 6” W x 6.5” H |
| Minimum Tank Size | 0.5-Gallon |
| Airline Input Size | 1/4" OD Airline |
AIR COMPRESSOR SPECIFICATIONS
| 12-Volt Light-Duty Compressor | |
|---|---|
| Part Number | Model 6270RC |
| Warranty | 1-Year |
| Max Pressure | 120 PSI |
| Duty Cycle | 25% @ 100 PSI (@ 72° F) |
| Flow Rate | @ 0 PSI (13.8 Volts): 1.56 CFM |
| Compressor Type | Waterproof Sealed, Oil-less |
| Voltage | 12-Volt DC |
| Motor Type | Permanent Magnetic Motor |
| Max Tank Size | 0.5 Gallon |
| Max Amp Draw | 14 Amps |
| Dimensions | 6.4” L x 3.5” W x 4.6” H |
| Mounting Holes | 6.14” L x 2.76” W (5mm Diameter) |
| Mounting Note | Mount in any position except upside down |
| Shipping Weight | 7 lbs |
| Pressure Switch/ Safety Valve HK1-HK2 | P/N 2121 (Pair w/ 52145 for 120 PSI kits) |
| Pressure Switch/ Safety Valve HK3-HK4 | P/N 2131 (Pair w/ 52155 for 130 PSI Kits) |
AIR TANK SPECIFICATIONS
| 1-Gallon Air Tank | |
|---|---|
| Part Number | Model 6270RT |
| Warranty | 1-Year |
| Tank Capacity | 1.0-Gallon |
| Construction | All Steel Design (Gloss Black Epoxy Finish) |
| Internal Coating | Internal Cortec Coating for Corrosion Resistance |
| Mounting Legs | 1 Leg w/ 2 Mounting Points |
| Air Tank Ports | 5 - 1/4" NPT Ports |
| Mounting Hardware | Fitting Pack - 2 Bolts, Nuts, Washers |
| Max Pressure | 150 PSI |
| Dimensions | 11” L x 6” W x 8” H |
AIR TANK FILL RATE DETAILS
| Tank Capacity | Tank Pressure Range | Tank Fill Rate |
|---|---|---|
| .5 Gallon | 0 - 150 PSI | 1 Min. 11 Sec. (+/- 5 Sec.) |
| .5 Gallon | 110 - 150 PSI | 26 Sec. (+/- 3 Sec.) |
| 1 Gallon | 0 - 150 PSI | 1 Min. 57 Sec. (+/- 10 Sec.) |
| 1 Gallon | 110 - 150 PSI | 38 Sec. (+/- 5 Sec.) |
INSTALLATION INSTRUCTION LINKS:

$390.95
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.
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.
This warranty does not cover damage or failure resulting from:
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.
To request warranty service, email warranty@kleinn.com with the following information:
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.
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.
Merchandise that has been worn, used, or altered will not be accepted for return or exchange.
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.