If your garage runs on Worx 20V Power Share, you already own the expensive half of a train horn: a high-output lithium pack. A Worx train horn clicks onto a battery you already have and turns it into a 140 dB blast — no adapter, no wiring, no compressor and tank. Here's exactly how compatibility, loudness, and runtime work on the Power Share platform so you know what to expect before you buy.
Will it fit my Worx 20V packs? (Short answer: yes, all of them)
Worx 20V Power Share is the orange-and-black cordless platform you'll find at retailers like Lowe's and direct from Worx, and the whole point of the system is that one battery foot serves the entire 20V line. The packs come in a handful of capacities split across two families: standard PowerShare in 1.5 Ah, 2.0 Ah, and 2.5 Ah, and the high-capacity PowerShare PRO in 4.0 Ah, 5.0 Ah, and 8.0 Ah, under model numbers in the WA36xx range (WA3575, WA3669, WA3674, WA3675, WA3678, and so on).
The labels look different, but the platform is simple: every Worx 20V Power Share battery rides on the same slide-mount foot and is interchangeable across the 20V line. A 2.0 Ah starter pack and an 8.0 Ah PowerShare PRO drop onto the exact same rail. For a train horn, that means the horn is built around the Worx 20V foot, and any 20V Power Share pack you own slides straight on. The bigger packs just give you more blasts per charge.
What "Power Share" actually is (and why the horn only needs one pack)
Power Share is Worx's name for the idea that the same 20V battery can power tools across its 20V, 40V, and 80V ranges. The trick on the bigger tools is simple stacking: you load two 20V packs side by side and the tool runs them in series for 40V, or four for 80V. It's a tidy system if you've bought into it, because one pile of identical batteries feeds everything from a drill to a mower.
Here's the part that matters for a horn. A train horn is a single-20V-foot device — it draws from one pack, the same way a 20V drill or impact driver does. You don't need a 40V or 80V tool's worth of batteries, and you don't stack anything. Any single Worx 20V Power Share battery in your collection runs the horn on its own. If you've been buying Power Share packs for years, the horn is just one more tool that shares them.
What "20V" actually means (and why it's the same as 18V)
Like "20V MAX" on DeWalt and Craftsman packs, the "20V" badge on a Worx battery is a peak number, not the running voltage. A Worx 20V pack is five 18650-class lithium cells wired in series. At 4.0 volts per cell straight off the charger that reads 20V, but at the 3.6V nominal each cell actually holds under load, the pack runs at about 18V. For all practical purposes a "20V" Worx battery and an "18V" battery from another brand are the same thing — it's a labeling convention the whole industry settled on when lithium replaced the old 18V NiCad packs.
The practical upshot for a horn: the horn's loudness is set by its trumpets and compressor design, not by the battery, so a Worx Quad is exactly as loud as any other Quad we build. What the pack contributes is the steady, high-current push the little compressor motor needs to build trumpet pressure — which is why pack quality and capacity matter more than the number on the label.
How loud is it, and what 140 dB really means
Battery train horns are sorted by trumpet count, and trumpet count is really a decibel-tier decision. Our Worx model is the Quad — four trumpets, rated around 140 dB. For reference, here's how the tiers stack up across our lineup:
- Dual (around 130 dB) — two trumpets. Plenty for a truck, boat, or UTV; roughly a jet taking off a couple hundred feet away.
- Quad (around 140 dB) — four trumpets, a fuller chord and more reach. This is the Worx 20V tier.
- Extreme Series (150 dB+) — four upgraded trumpets tuned for a deeper, louder tone that carries farther.
Decibels are logarithmic, so the step from 130 to 140 dB is a far bigger jump in sound energy than the numbers suggest — and 140 dB is a level to respect. A stock pickup horn lives down around 100–110 dB, so a Quad is many times the acoustic energy of the factory horn it sits next to. OSHA's longstanding policy is that impulse or impact noise should not exceed 140 dB peak, which is also right around the threshold of pain for human hearing. The takeaway from the U.S. OSHA occupational noise guidance: keep your distance from the trumpets when you fire it, and treat hearing protection as smart, not optional, if you're standing close. For how the same tiers play out on other battery systems, our Milwaukee M18 vs DeWalt 20V train horn comparison walks through the dB ladder platform by platform.
Runtime: what your Worx packs actually deliver
A train horn isn't a steady drain like a flashlight — it's a compressor that pulls a hard slug of current to build pressure, then tapers off. Two things drive how long a Worx pack lasts on the horn: capacity (amp-hours) and how well the cells handle that startup surge.
Capacity is the easy part — more amp-hours, more blasts. A 1.5 Ah or 2.0 Ah standard PowerShare pack keeps the whole rig light and is fine for occasional fun. A 4.0 Ah, 5.0 Ah, or 8.0 Ah PowerShare PRO pack gives you far more honks between charges and is the better pick if the horn lives on a work truck, a boat, or the farm. The surge is the part people forget: the PowerShare PRO line uses higher-output cells with a battery-management and cell-cooling design, so it delivers current more readily — building trumpet pressure a touch faster and sagging less on a long lean-on-the-button blast. None of this is unique to Worx; it's how every battery horn behaves. We run the full math, including how many blasts each Ah rating buys you, in does battery Ah affect runtime and loudness.
The Power Share ecosystem angle
The biggest benefit of a Worx horn isn't a spec — it's that you're not buying into a new battery system. If your drill, blower, and yard tools already run on Power Share, the horn just becomes one more tool on the shelf that shares your packs and your charger. That's the whole appeal of a battery train horn over an old-school compressor-and-tank setup.
It's worth knowing how Worx backs the packs themselves, since that coverage follows the battery, not the horn. Worx covers standard PowerShare batteries with a 3-year warranty and the PowerShare PRO high-capacity line with a longer 5-year warranty against defects in materials and workmanship. So whichever pack ends up powering your horn is backed on Worx's own terms, independent of the horn you mount it on.
Which Worx horn should you buy?
For the Worx 20V Power Share platform we build the Quad — the four-trumpet, ~140 dB tier that's the sweet spot for trucks, farms, boats, and anyone who wants real reach without stepping up to a premium horn. It mounts on any 20V Power Share pack you own:
- Quad Train Horn for Worx 20v Battery — four trumpets, ~140 dB, native Worx 20V foot, wireless remote included.
The Worx version is the same horn we build for every major platform — the only difference is the battery foot. Our flagship is the Extreme Series Train Horn for Milwaukee® 18v Battery, and the Worx Quad uses the same style of trumpets and compressor with a Worx 20V foot instead of an M18 one. So being on the Power Share system doesn't get you a watered-down horn — you get the same hardware, matched to the packs already in your garage.
Shopping across battery brands? The same compatibility-and-runtime breakdown exists for the other big platforms — see our Makita 18V LXT train horn guide and our Kobalt 24V train horn guide for the same rundown on those systems.
FAQ
Does the Worx horn work with all 20V Power Share batteries?
Yes. Every Worx 20V Power Share pack — from the 1.5 Ah and 2.0 Ah standard batteries up to the 8.0 Ah PowerShare PRO — uses the same slide-mount foot and is interchangeable across the 20V line. The horn doesn't care which one you use; higher-capacity packs just give you more blasts and a faster pressure build.
Is a Worx 20V battery really 20 volts?
It's a peak rating measured straight off the charger. The running (nominal) voltage is about 18V — five lithium cells at 3.6V each. That's the same marketing convention DeWalt uses with 20V MAX and is completely normal; a "20V" Worx pack and an "18V" pack from another brand are effectively the same voltage.
Do I have to stack two batteries like on a 40V Worx tool?
No. Stacking is only for Worx's 40V and 80V tools. The train horn is a single-20V-foot device, so one Power Share pack runs it on its own — no stacking and no adapter.
How loud is the Worx train horn?
The Worx model is our Quad, rated around 140 dB. Because 140 dB is the level OSHA treats as the ceiling for impulse noise, give the trumpets distance when you fire it and wear hearing protection if you're standing close.
Do I need an adapter to run a Worx pack on the horn?
No. We build the horn with a native Worx 20V foot, so the pack mounts directly with no adapter in the current path — which matters for a high-draw compressor load.