As an electrical engineer I would have to say yes. You are simply stepping down the voltage. 135 watt is really quite small. I would hesitate to use a hair dryer for example, because they need 1,000 - 2,000 watts.
check the wattage on your flat iron. If it's over 200 W, then definitely not, and even if it's approaching 200W I'd be wary of using it for more than a couple minutes at a time. That being said, if it's like 150W or lower, you're probably fine, and if you're closer but not over you're probably still okay as long as you exercise some caution. My experience is, if it overstresses the converter, it trips some thermal switch that just shuts down the device. Once it cools, it'll be good to go again.
You need to think about two things when you travel. A converter and an adapter. This step down is a converter that is no longer necessary as it steps down your razor, and small digital items like your camera, your cell phone, your iPad. We found that all of these small items manufactured in the last 4 years have a built in converter. Read the plug on your travel items. It will tell you if it has a built in converter. Next is the adapter. This inexpensive piece connects to your electronics to match the holes in Brazil's wall receptacles. I would suggest this from Amazon: Adapter Plug Brazil A, B and GUZ. Hair Care products are a whole different animal. I suggest purchasing in Brazil if necessary. Hope this helps you.
I used it in Italy and France not in Spain not so sure about the wall outlets in Spain. If your Device/s charger is made for US then yes you would need it. it is a good hardy unit, it served me well. Using a regular power strip for US connected to this I charged three cell phones one GPS a tablet and a camera battery charger at the same time,this was done over night for next day usage, I did this for twelve days in a row; it worked very well. I do not think you can use it with anything with heating elements like an Iron made for US a curling iron or a hair dryer.
More than likely, yes you will need some type of voltage/wattage converter. However I'm not sure what India uses in terms of power whether it's 110 or 220, may want to Google that if you're unsure. Two quick thoughts though, I'd personally suggest not to buy this particular unit. Went through two of them and they both crapped out on me after a day.
Second go to an electronics store like radio shack or maybe amazon has them as well. But you'll probably want to find an adapter that can plug into the type of plug used in India.
If you don't understand the difference between an adapter and converter think of it this way. An adapter is like using a micro SD card, but your camera takes a full size SD card, so you get an adapter to make it full sized.
The converter regulates the power coming out of the wall, which is what this product on this page will do.
Sorry if that was redundant, but sometimes people need it spelled out. Enjoy your trip though!
I thought this unit was pretty heavy but I used it in Germany to charge my DS and it worked perfectly. Not sure if the voltage is the same in India as the European nation, but it worked for me. Hope that helps
It should since the light doesn't pull a lot of amps. I'm in Austria right now and using mine to charge my laptop, my Nook, and iPhones. I also use it for my curling iron......but you can't use it with a blow dryer. Our friends here did that a few days ago and burned up her hair dryer and tripped the hotel breaker. :D
I don't have a PS4 but look at whatever it says for power requirements. I fit says you can use "100V to 240V AC; 50/60HZ" then all you would require is a Adapter plug to allow the USA Plug to connect to European or whatever power connector you want to connect with. Many electronics today will accept a wide range of input voltages around the world and only need the right plug to work with this.
Hope this helps........