VEVOR HS-550 4-Trumpet Air Horn Kit with 12V Compressor: specs explained

The VEVOR HS-550 is an air horn kit with four trumpets, an onboard compressor and a small air tank, designed to run from a 12V vehicle electrical system. It replaces or supplements a standard car horn with a much louder, deeper note. Because a horn this loud affects other road users, local rules matter as much as the specs.

What is in the kit

VEVOR lists four trumpet horns, a solenoid valve, a 0.8-gallon (3 L) tank, a compressor and pipes. The listing notes that the power switch and cord are not included, so you'll need to source your own switch, and wiring that suits the compressor's current draw. The whole kit weighs 12.1 lb (about 5.5 kg) and measures roughly 11 x 5.5 x 5.5 inches (28 x 14 x 14 cm).

How an air horn works

The compressor fills the tank with air. When you press the horn button, the solenoid valve opens and the stored air rushes through the trumpets, making them sound. A tank means the horn gets a burst of air at once, rather than relying on the compressor alone. That is why air horns can be so much louder than electric disc horns.

The 90 to 120 psi range

VEVOR says the compressor works between 90 and 120 psi (about 6 to 8 bar). It starts when pressure drops below 90 psi and stops above 120 psi, so the tank refills automatically after use. A gauge lets you read the pressure. The listing also mentions fuses to protect the compressor and a drainage plug to release the water that condenses in any compressed-air tank.

What 150dB means

VEVOR rates the kit at 150dB. Decibels are logarithmic, so small increases mean large jumps in sound energy, and 150dB is far above what a car horn typically produces. Such a figure is measured under particular conditions, and the sound you hear will vary with distance and mounting. Sound at this level can damage hearing at close range, so mount the trumpets away from where people stand, and follow the manual.

Build and mounting

The kit uses zinc alloy and steel with an anti-rust coating. VEVOR says the compressor has a non-leakage structure and a welded tank. A thick rubber cushion goes between the tank and the vehicle's underside to reduce vibration and noise. The air pipe is stated to tolerate 120°C, and the motor has a 100°C overload protection. Mounting position matters, so keep the compressor and wiring away from sources of heat and water.

Vehicle compatibility

VEVOR describes the kit as universal for any vehicle with a 12V battery system, listing trucks, SUVs and boats. Check the space available under the vehicle or in the engine bay.

Check the rules first

Many places limit horn volume or restrict the use of train-style horns on public roads, and some treat them as off-road or show use only. Check your local and provincial or state regulations and your vehicle inspection requirements before fitting one.

What to check before you buy

• Legality: confirm what is allowed where you drive.
• Space: you need room for the tank, compressor and four trumpets.
• Switch and wiring: buy a suitable switch, fuse and cable, since they are not included.
• Voltage: the kit is for 12V systems only.
• Mounting spot: choose a location that is protected from road spray and heat.
• Upkeep: drain condensation from the tank regularly, as the manual describes.

The short version

• VEVOR HS-550: a four-trumpet air horn kit rated by VEVOR at 150dB.
• 0.8-gallon tank and a compressor that cycles between 90 and 120 psi.
• Includes horns, solenoid valve, tank, compressor and pipes; no switch or cord.
• Runs on 12V; weighs 12.1 lb.
• Check local noise and road-use rules before installing.

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