Modified sine is cheaper, and some appliances refuse it outright · review

Green Cell 300 W pure sine, 12 V to 230 V, 600 W peak review

A 300 W pure sine inverter with a 600 W short-term peak, mains sockets and a USB port for small devices, sold with safety certifications named but not identified.

By Jean-Benoit Buisson

The bottom line A simple, inexpensive pure sine inverter with a useful USB port and a listing that names not one of the certifications it claims. Four of its seven specification lines are empty.

A 300 W pure sine inverter sold on simplicity.

What it is for

Running 230 V equipment from a 12 V battery, with 300 W continuous and up to 600 W briefly. A mains socket and a USB port, so a phone can be charged without going through the inverter at all.

The claim that cannot be checked

The fourth bullet describes a range of safety features and safety certifications. Not one is named. A certification is a standard and a body — naming neither makes the claim unverifiable, and three inverters in this family do name theirs.

The title to read carefully

“300W/600W” in the same phrase. The first bullet makes the relationship clear — 300 W continuous, up to 600 W briefly — but the title presents them as equals, and a peak read as a rating is the commonest sizing mistake on this shelf.

The four blanks

Idle consumption. Efficiency. Cooling. Input voltage range. On a small inverter the first is the one that matters most: left switched on, it draws from the battery whether or not anything is plugged in, and no figure is published.

Availability

German Amazon store quoted about 49 € when this page was compiled.

American Amazon store carries it too, priced in its own currency, which the euro range above deliberately omits.

British, French, Italian and Spanish Amazon catalogues carry an entry for it, with nobody selling.

These figures are what Keepa reported on the day this page was last updated. Availability and pricing move without notice.

Prices quoted in this text were read on 16 September 2026. The live price is at the top of the page.

What it gets right, and what it leaves out

Strengths

A USB port alongside the mains socket, so small devices bypass the inverter stage
The peak is described as short-term rather than presented as a second rating
The lowest-priced pure sine inverter in this family

Compromises

Protections and certifications are claimed without a single one being named
No idle consumption, no efficiency, no cooling description
The title lists 300 W and 600 W together, which invites the peak to be read as continuous

Specifications

Waveform	Pure sine, from the title
Continuous and surge output	300 W continuous with a short-term peak up to 600 W, first bullet; the peak carries no duration
Idle consumption	Nowhere in the listing
Efficiency	Nowhere in the listing
Input range	12 V battery, first bullet; no voltage range is published
Protections	Described as a range of safety features and certifications, fourth bullet; none is named individually
Cooling	Nowhere in the listing
Amazon reference	DE B0744LR2DZ · US B086PB21S5 · GB B086PB21S5 · FR B086PB21S5 · IT B086PB21S5 · ES B086PB21S5
EAN	5902719422249

Questions owners ask about this one

Why does the USB port matter on an inverter?

Because a device charged over USB skips the conversion to 230 V entirely, which removes a loss. On a small inverter running from a car battery, that is the difference between charging a phone efficiently and charging it through two conversions.

What should be made of unnamed certifications?

Very little. A certification is identified by a standard and a body; a claim that certifications exist, without naming any, cannot be checked. Three other inverters in this family name theirs.