Worx built its PowerShare platform around one promise: every 20V battery runs every tool, from a drill to a string trimmer to half of a 40V mower. A battery-powered train horn keeps that promise going — the same orange-capped pack that edges your lawn will fire a 140 dB quad horn. Here's exactly which PowerShare packs fit, what the 20V label really means, and how many blasts each size gives you.
The short answer: every Worx 20V PowerShare pack fits
A battery train horn is built like a cordless tool. Inside there's a compressor, a set of tuned trumpets, and a battery dock molded for one specific platform. Slide your pack onto the rails until it clicks, and the horn is live — no air tank, no wiring, no adapter. BossHorn builds a dedicated Worx dock: the Quad Train Horn for Worx® 20v Battery, a four-trumpet unit with a max output of 140 dB and three volume settings (roughly 110, 130, and 140 dB), audible up to a mile out. It accepts Worx 20V packs from 2.0 Ah up to 12.0 Ah, and aftermarket 20V-compatible packs mount the same way.
So the real question is never "is my PowerShare pack strong enough" — it's "does this horn have a Worx dock." It does. The battery you already rotate between your trimmer and your drill is the whole power system.
What "20V" means on a PowerShare pack — Worx already told you
Most tool brands make you dig for this, but Worx puts it right in the product name: the company has sold its 2.0 Ah pack under the label "18V & 20V MaxLithium." Both numbers describe the same battery. The pack is built from lithium-ion cells that sit around 3.6 volts each under load; five in series gives you 18 volts nominal — the working voltage. Freshly charged with no load, each cell reads closer to 4 volts, and five times that is where "20V MAX" comes from. Worx simply prints both readings.
What that means for the horn: a Worx 20V pack is the same 18-volt class as a Milwaukee M18 or a Ryobi ONE+ pack, and it delivers every volt a 140 dB quad horn is engineered for. The compressor reads volts and draws amps — it doesn't care whose name is on the pack. And the duty cycle is about the friendliest you can hand a battery: a horn fires in one- and two-second bursts, not the sustained minutes a mower or saw pulls.
Which PowerShare batteries fit: standard, PRO, and aftermarket
PowerShare is one platform — Worx states that its standard and PRO batteries are compatible with all of its 20V, 40V, and 80V garden, lifestyle, and power tools, regardless of amp-hours, across a catalog of 140+ products. There's no high-power-only sub-line that locks a pack out, and the same applies at the horn's dock. The lineup breaks down like this:
- PowerShare standard — 1.5 Ah, 2.0 Ah, 2.5 Ah. The compact packs that ship with most Worx lawn and DIY tools. The horn's spec sheet lists compatibility from 2.0 Ah up, so the 2.0 and 2.5 Ah packs are your entry points here.
- PowerShare PRO — 4.0 Ah, 5.0 Ah, 8.0 Ah. The higher-capacity line with an intelligent battery-management system that monitors cells to optimize power and runtime. Same rails, same fit — just more energy in the box.
- Aftermarket 20V-compatible packs. Third-party Worx-compatible batteries are sold well past the factory sizes — the horn accepts packs up to 12.0 Ah. If it mounts on your Worx tool, it mounts on the horn.
One quirk worth knowing if you own Worx 40V or 80V yard tools: those don't use a different battery. A 40V Worx tool runs two 20V packs at once, and an 80V tool runs four. So even the batteries powering your "40V" mower are, individually, 20V PowerShare packs — and any one of them runs the horn.
How long they run: blasts per charge by pack size
Loudness comes from voltage; blast count comes from amp-hours. A 1.5 Ah pack fires the horn at the exact same 140 dB as an 8.0 Ah pack — the small one just runs out of blasts sooner. BossHorn rates the Worx quad at 500+ short blasts (or about 200 sustained ones) on a 6 Ah battery, and because horn use is short bursts, capacity scales almost linearly. Here's what that math looks like across the PowerShare lineup:
| Pack | Approx. short blasts | Best for |
|---|---|---|
| 2.0 Ah standard | ~165 | The pack many Worx kits ship with. Plenty for a weekend of camping or trail runs. |
| 2.5 Ah standard | ~200 | A bit more headroom, still light on the horn. |
| 4.0 Ah PRO | ~330 | The everyday sweet spot for regular signaling. |
| 5.0 Ah PRO | ~415 | All-day events without a spare in the truck. |
| 8.0 Ah PRO | ~650 | Maximum blasts between charges — leave it on the horn. |
Those are estimates scaled from the tested 6 Ah figure, and real numbers move with temperature, blast length, and pack age. But the practical takeaway holds: even a compact 2.0 Ah pack that came with your trimmer is good for 150+ full-volume blasts, which is more than most people fire in a season.
Where a Worx horn earns its keep
Worx built its base in the yard — mowers, trimmers, blowers, hedge tools — which means PowerShare owners skew toward people with property. That's exactly where a portable 140 dB horn does real work: clearing deer and coyotes off a garden or field, moving stubborn livestock, hailing someone across acreage without a phone, or putting an unmistakable warning blast down a shared driveway.
It travels, too. The whole unit weighs about 4 pounds and needs nothing bolted to a vehicle, so it rides in a UTV cargo box, a boat locker, or behind a truck seat. The included wireless remote fires the horn from up to 160 feet, and an optional long-range remote stretches that to 2,000 feet — useful when the horn is mounted in the truck bed and you're not in it.
If you ever chase the absolute loudest tier and don't mind a second battery ecosystem, that crown sits with the 150 dB+ Extreme line — for example the Extreme Series Train Horn for Milwaukee® 18v Battery. But there's no need to switch platforms just to get loud: the Worx quad already hits 140 dB on the packs charging in your garage right now.
FAQ
Do PowerShare PRO batteries work on the horn, or only standard packs?
Both. Worx states that standard and PRO batteries are compatible with every PowerShare tool regardless of amp-hours, and the horn's Worx dock follows the same interface. A 4.0, 5.0, or 8.0 Ah PRO pack mounts exactly like a 2.0 Ah standard pack — you just get more blasts per charge.
Will an aftermarket Worx-compatible battery run the horn?
Yes. The horn accepts 20V Worx-compatible packs from 2.0 Ah up to 12.0 Ah, including third-party batteries, as long as they mount on the standard PowerShare rail. If a pack runs your Worx trimmer, it runs the horn.
Does a small 2.0 Ah pack make the horn quieter?
No. Volume comes from voltage, and every PowerShare pack — 2.0 Ah or 8.0 Ah — delivers the same 18 volts nominal. A smaller pack only means fewer blasts before a recharge.
I own Worx tools but my buddy runs Ryobi. Same horn?
Same horn family, different dock. The battery feet are shaped differently between brands, so packs don't cross over directly — BossHorn builds a separate model for each platform. There are also cross-brand adapters, with caveats we've covered in our adapter guide.
Do I need to buy a battery from BossHorn?
No. The point of the Worx-specific dock is that your existing PowerShare packs work. Compatible 20V batteries and chargers are sold as optional add-ons for buyers who'd rather keep their tool packs on the tools, but they're not required.