3000W ST-Pro Auto Step Up & Step Down Voltage Transformer Converter, Heavy-Duty AC 110/220V Converter with US Standard, Universal, Schuko AC Outlets & DC 5V USB Port by Goldsource [3-Year Warranty]

Works very well.. Be careful of the weird combo multi adapter plug that will allow 220vac and 110vac to work on the same plug. I'll never understand why that is not a code violation.

It's a bit bulkier than I would like but given the wattage it supports, I can deal with the thing sitting on the kitchen floor. I've already used it with all my 220v appliances and they all function normally. I used my Panasonic rice cooker and rice was cooked with no issue in 50min. I used it with the electric kettle and the toaster and both did their jobs as before. I also vacuumed the entire apartment with my Dyson canister without any issue. It was quiet without any unusual noise or humming during usage. It is quite versatile with both step-up and step-down functions but I seriously doubt I would ever need it to step down from 220v to 110v. The separate power input sockets are clearly marked for 110v or 220v. Since this is sold in the US, it only comes with a US plug power cord. For those looking to use it for step-down, you'll have to find a cord with the plug type you need. There are two 110 outlets and two 220 outlets with one being universal (fit my UK type plugs) and one three-prong type (not sure what it is). The strap on top makes it easy if you do need to move it around. For under $120 it's a pretty good deal as it enables me to use my existing appliances, especially the Panasonic and Dyson without having to buy new ones, which will cost me way more than $120. Update Feb 2023: After 3 years of continuous usage with vacuum cleaner, rice cooker, electric kettle, and toaster, it finally started having problems. It starts to emit burning smell while using with the kettle and the vacuum. There is no fume nor the unit is excessively hot. However, on the safe side, it's time for a new one.

This put out the power and doesn't get very hot. I haven't hooked it up to a meter to measure it's actual power efficiency yet. I am using it to run a 1600W 240V heater. Normally you want at least double head room when using a power transformer with a heater. I.e. a 1600W heater should have a 3200W transformer. Yet this doesn't even get hot. It is very easy to use, even without an owners manual as all the outlets and ports are clearly marked. Even the 2 fuse ports have the fuse size printed beneath them. I couldn't be happier with this! :-)

This is an auto-transformer. As it only has three leads on the transformer, it provides no isolation. If you use it to step up voltage, the output will be 230 volts relative to neutral or ground. Twice the usual. I plan to use this with a generator to power my well pump during power outages so the isolation isn’t an issue. I took the cover off to check the circuit and found a wire soldered improperly to one of the outlets. This was a 12 Ga wire held on by only a couple of strands. I wasn’t planning to use this outlet but it could have broken off and made a dangerous situation. Update. After testing for a few hours, the fuse holder failed. Poor contact to fuse and holder led to bad electronic smell. Had to replace fuse holder. Poor quality, unreliable unit.

My wife is from Beijing so she has a number of appliances that run off of 220V. This device allows us to use them here in the states with no issues. She had a small cheap transformer prior to this that died shortly after use but this beefy thing definitely does the job and does it well. It is heavy so not sure that I would ever travel with it but for use here at home, it works perfectly.

I have a machine from Asia. It wouldn’t plug into the universal port. Almost like something inside the port was block the plug from inserting all the way in. We had to swing by frys electronic to get a universal adapter that looked the exact same as the port. But for some reason, we were able to plug into the $6 adapter and using that, plug into the common USA port. Other than that, the machine worked fine and instructions super simple to follow.

Fantastic product. I work for the government, and I just returned from five years in Germany. I didn't want to get rid of all the 220 products we had purchased there. This transformer is great, and I use it for all of my German devices that I'm still using. The only drawback, which is totally expected, is that it's really heavy. It's not something that you'd bring on vacation, unless you can bring a heavy brick with you.

I'm in the U.S. I bot the 3000W amazon product so I could use my eu2000i (110V)generator to run my 220V propane forced air heater if power goes out. It is a propane forced air unit with 3/4 hp blower motor and a small combustion fan. It is around 700W total. My heater is a 240V unit....and it is PURE 220. It's only fed by 2 hots and a ground. There's no center tap (neutral wire) for 110v. Only 3 wires go to the heater. If you are trying to run an appliance that has to tap of 110V from neutral and one leg of the 220 (ie 4 wires= 2 hots, 1 neutral and 1 groundlike most US utilities), Then this amazon product would probably NOT work. So this amazon product worked for me.