HornAir 4485K Nightmare Edition Onboard Air System

Premium Kit W/ Quick Filling & Heavy Duty Onboard Air


Add Viair Air Compressor Bracket Tooltip
The Viair Air Compressor Bracket will allow you to mount your compressor upright and is compatible with Viair Compressor models 275C-485C.
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Add 220 PSI Digital Pressure Gauge Tooltip
Using a tank mounted sensor wired directly to your gauge, our 220-PSI rated Digital Air Pressure Gauge delivers unparalleled accuracy with microprocessor stabilized readings.
Add Cooling Fan Isolator Kit Tooltip
Isolate your Compressor, drastically cutting down on vibration, allowing your compressor to run quieter & cooler, & extending the duty cycle up you 25%!
Add Gold Extended Warranty Tooltip
1 year add-on to existing warranty. Does NOT cover accidental damage, no advanced replacement.
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Add Platinum Extended Warranty Tooltip
2 year add-on to existing warranty. DOES cover accidental damage and advance replacement.
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This kit is not to be underestimated. Despite it having a 4-gallon reservoir, the included air pump is an absolute powerhouse. This Viair 485C is the most heavy-duty air compressor that Viair offers. It’s designed specifically for smaller vehicles where larger tanks may not fit. The compressor is overpowered (200 PSI capable, constant duty, and powerful!) to ensure the best reliability, and only pulls 22 amps at its peak.

Included is our matching black 4-gallon pancake air tank that has four 1⁄2” ports on top, two 3⁄8″ ports on top, one 1⁄8” port on top, and one 1⁄4” port on the bottom. Strategic placement of the ports allows you to be able to install your drain cock on the bottom-most port on the tank for optimal draining no matter how the air tank is oriented. The ½ inch ports provide optimal airflow, preventing bottlenecking that occurs in other kits. This tank is great for stashing in a wheel well or other areas you need a 4-gallon air tank in a tight spot. 

An increasing number of people are using this for more than just blasting horns! With a system like the 4485K, you can also use the air supply to:

  • Adjust tire pressure
  • Moderate pneumatic use
  • Inflate water toys and safety gear
  • Supply air to load leveling bags
  • Supply air for differential lockers
  • Blow up kids toys
  • And lots more!

Please note that if you use horns, you will still need an air valve kit to connect the system properly. 

Unlike some other air systems, HornAir onboard air systems come with 10 and 18 gauge wire and a complete wiring kit including a fuse holder. This takes out the guesswork on your end and helps ensure your system is installed correctly. Another great feature of HornAir systems is that they come with a standard 1/2in OD push-to-pull fitting. This means the horns you hook up with get all the air they need.


Shocker S4 train horns (part number: AH-S4)
Outlaw series train horns (part numbers: AH-O3, AH-03B, AH-O5)

    0 2.24 12 0 70.0 12
    10 1.84 14 1.0 51.0 15
    20 1.75 16 2.0 47.0 16
    30 1.67 17 3.0 44.0 18
    40 1.61 18 4.0 41.0 20
    50 1.54 19 5.0 38.0 21
    60 1.47 20 6.0 35.0 21
    70 1.42 21 7.0 32.0 22
    80 1.36 21 8.0 29.0 22
    90 1.30 22 9.0 27.0 22
    100 1.23 22 10.0 25.0 23
    110 1.17 22 11.0 22.0 22
    120 1.11 22 12.0 21.0 21
    130 1.06 22 13.0 21.0 21
    140 1.01 23 13.8 21.0 21
    150 0.97 22      
    160 0.92 22      
    170 0.88 22      
    180 0.84 21      
    190 0.77 21      
    200 0.73 21      

    * Supply Voltage: 13.8 Volts

    • All-inclusive train horn air solution!
    • Top-End 200 PSI capable compressor perfect for train horns
    • Comes with a standard 1/2" push-to-pull fitting
    • Complete fitting kit with safety valve & drain cock
    • All standard mounting hardware
    • Part Number: HA-4485K
    • Operating Pressure: 150 PSI
    • Restart Pressure: 110 PSI
    • Voltage: 12-Volt DC
    • Air Tank: 4-gallon pancake air tank
    • Air Tank Volume: 4 gals (15.14 L)
    • 1/4" NPT Ports: 1
    • 1/2" NPT Ports: 4
    • 3/8" NPT Ports: 2
    • 1/8" NPT Ports: 1
    • Tank Length: 16″ (406.4 mm)
    • Tank Width: 16″ (406.4 mm)
    • Tank Height: 8″ (203.2 mm)
    • Max Amperage: 23 amps
    • Air Compressor: Viair 485c air compressor
    • Average Fill Time: 1 Min 30 sec
    • Air Flow: 2.24 CFM at free flow
    • Maximum Duty Cycle: 100% @ 200 PSI
    • Compressor Length: 10.63″ (270 mm)
    • Compressor Width: 4.1″ (104.14 mm)
    • Compressor Height: 6.44″ (163.57 mm)
    • Money-Back Guarantee/Refund Policy
      All merchandise unless otherwise indicated 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. A 15% restocking fee may apply. Additional deductions may be made to reflect the products current market value. These terms apply to all refunds. Most products are shipped with a refund/replacement guarantee period unless otherwise noted in the product listing. Customers must inform HornBlasters.com of any order discrepancy within 7 days from the invoice date so that we may investigate and resolve the situation accordingly.
    • Warranty
      This product is backed by our one-year manufacturer's defect warranty!
    • HornBlasters.com Satisfaction Guarantee
      HornBlasters.com offers our customers a 30-day satisfaction replacement or refund guarantee on all purchases, except when otherwise noted in the product listing.
    • Cross-Shipments
      HornBlasters.com will not cross-ship returned merchandise.
    • Physical Damage Policy
      Physical damage to any product purchased at HornBlasters.com will effectively void warranty coverage. Physical damage includes but is not limited to improper handling and/or any other type of damage sustained by irregular usage.

    Warnings & Notices

    Safety warning icon

    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.

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