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StopWatt

Specs

StopWatt technical specifications

This page states the technical detail of the device plainly, with no rounding up. Use it to confirm compatibility with your outlets and to plan how many units your home needs before you order.

By the StopWatt official store teamUpdated

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Quick answer

StopWatt operates on 90V-250V AC at 50 or 60 Hz through a standard grounded household outlet, which covers US residential power and most international supplies with the right plug adapter.

What are the electrical specifications?

SpecificationDetail
Device typePassive plug-in power-factor correction unit
Operating voltage90V - 250V AC
Frequency50 / 60 Hz
ConnectionStandard grounded household wall outlet
Status indicatorLED confirms the unit is powered and active
Coverage guidanceApproximately 800-1,200 sq ft per unit
Power drawMinimal standby draw for internal circuitry only

Is StopWatt compatible with my home's outlets?

SetupCompatible?Notes
Standard US 120V grounded outletYesMost common residential setup
International 220-240V outletYes, with plug adapter90V-250V range covers most countries; adapter may be needed for socket shape
Power strip or extension cordNot recommendedPlug directly into the wall for correct operation
GFCI or AFCI outletYesWorks normally on protected circuits
Ungrounded two-prong outletNoRequires a standard grounded outlet

What is inside the housing?

  • Flame-retardant housing with a standard grounded plug.
  • Capacitor bank sized for residential branch circuits.
  • Indicator LED that confirms the unit is receiving power.
  • No fan, no firmware, no moving parts, no audible operation.

What ships in each bundle?

See current StopWatt bundle pricing and where each price applies on our where to buy page.

BundleUnits includedAlso includes
1 device1Quick-start placement card, retail packaging
2 devices2Quick-start placement card, retail packaging
3 devices3Quick-start placement card, retail packaging

What are the usage limits?

  • Indoor use only; keep the unit dry at all times.
  • Plug directly into a wall outlet, never a power strip or extension cord.
  • Do not open, modify, or immerse the housing.
  • Discontinue use if the casing cracks or the unit feels hot, and contact support.

What is StopWatt not designed to do?

Read this before you install

StopWatt is not a surge protector, battery, generator, or meter-altering device. It does not store energy, does not power anything during an outage, and does not change what your utility meter records. It only affects power factor on the circuit it shares. See does StopWatt really work for how that connects to your bill.

How many units does my home need based on these specs?

Match unit count to square footage using the coverage guidance above: one unit for homes under 1,200 sq ft, two for 1,200-1,500 sq ft, and three for anything larger or multi-storey. Full placement guidance by room is on the installation guide.

If you are unsure which bundle fits your home, StopWatt bundle pricing breaks down the same sizing table alongside the cost for each option.

Ready to order the right bundle for your home?

Every order from this official store includes free worldwide shipping and a 60-day money-back guarantee on the purchase price, so you can confirm compatibility and test placement without financial risk. Buy StopWatt from the official store once you know your unit count.

60DAYS

60-Day Money-Back Guarantee

Test StopWatt for a full billing cycle. Return it within 60 days of delivery for a refund of the purchase price.

Issued by the official StopWatt store · Refund of the purchase price

Frequently asked questions

What voltage does StopWatt operate on?
StopWatt operates on 90V-250V AC at 50 or 60 Hz through a standard grounded household outlet, which covers US residential power and most international supplies with the right plug adapter.
Does StopWatt work on 240V circuits?
It works on a 90V-250V supply through a standard household outlet, but it is not intended for hard-wired 240V appliance circuits like an electric dryer or range.
Is it safe to leave plugged in continuously?
Yes. Continuous operation in a dry indoor outlet is the intended use, and the device has no moving parts or fan to wear out.
How much space does one unit cover?
Roughly 800-1,200 sq ft, though placement near your largest motor loads matters more than exact square footage.
Can I use it with a power strip?
No. Always plug directly into a wall outlet for correct operation and safety; power strips and extension cords are not recommended.
What comes in the box?
The number of units in your bundle, a quick-start placement card, and retail packaging suitable for gifting.
Is StopWatt a surge protector or battery backup?
No. It does not protect against surges and does not store energy for use during an outage. It is a passive power-factor correction device only.

Keep reading on the official StopWatt site

Ready to order? Buy StopWatt direct or compare StopWatt bundle pricing.

Order direct from the official store

Ready to try StopWatt risk-free?

Pick the bundle that matches your home size, then complete your order securely on this page — no redirects, no account required.

Sizing rule of thumb: one device per 800–1,200 sq ft, so most homes over 1,500 sq ft use the 3-device bundle.

Checkout — 3 Devices

$105.84

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  • Charged onceOne-time payment, no subscription
  • Dispatch1–2 business days, tracked
  • 60 daysReturn for a refund, no questions
  • Real supportsupport@getstopwatt.net

Prices in USD. The bundle price shown is the full discount — there is no code to hunt for. Add-ons available only here: add 1 extra stopwatt and 3-year replacement protection.