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Sigelei Fuchai Duo-3 Review Bottom Line

Sigelei is keeping up to date with market trends with the newest design in their Fuchai series. If you have heard of users who encountered problems with temperature control in TC mode with the original Fuchai 213, the Sigelei Fuchai Duo-3 175 TC Box Mod will fully restore your faith the Sigelei Fuchai series.

Full In-Depth Review of the Sigelei Fuchai Duo-3

The Sigelei Fuchai Duo-3 in red
There’s a growing new class of mods that lets you add extra batteries to the setup to increase wattage if you need it. One type is the WISMEC EXO Skeleton ES300 300W TC BOX, whose shape stays the same whether you use two or three batteries. The second type comes with an additional battery cover which you swap out when you add extra batteries Examples are the SMOK GX2/4 and the Teslacigs Invader 2/3. The Sigelei Fuchai Duo-3 175W TC Box Mod is currently available as a dual (duo) battery model or a slightly more expensive three-battery model which comes with two separate battery covers and lets you change the mod size and wattage as you please.

Let’s make one thing clear, there are 2 versions of this model on the market, the only difference being that one has an extra battery case to enable the three battery configuration, but it seems that Sigelei were in somewhat of a rush to get this product to market and therefore the initial products only come with the 2 battery case, you have to buy the extra case separately!The Sigelei Fuchai Duo-3 with 2 battery cover The two-battery config handles up to 175W, while the configuration with an extra battery (hence the name duo-3) will increase maximum output to an impressive 255W. Weird they called both versions the duo-3 although they both have the same capabilities!

Unfortunately, the 18650 batteries do not come with the device, so how do you choose the right ones! Well it depends on what tank and coils setup you have, and lucky for you, we have a guide to explain how to choose the right battery for your mod should you need it! Alternatively, you can just skip all that and take a look at the best 18650 batteries on the market!


Body Building

The new Fuchai Duo-3 mod is available in black, gunmetal gray, pale gold or pale silver, a fresh bright blue, and red. The chassis is constructed from a tough zinc alloy with a discreet texturized pattern of smooth micro-holes. The rounded edges look elegant and provide a comfortable grip. They have taken the ideas from their Sigelei Fuchei 213 and just improved it! In duo config the dimensions are 85mm tall, 42mm broad and 30mm wide (5.1” x 2.5” x 1.8”).
The Fuchai Duo-3 with both covers


Color OLED Screen

The OLED Screen on the Fuchai Duo-3
The full-color screen is an inch in size with a vertical color-coded layout that makes it easy to track operating mode, resistance and temperature when in TC mode, voltage and wattage, battery life, and a puff counter. The large asymmetrical firing button sits at the top, and adjustment buttons are positioned just below the screen. The Micro-USB port will allow firmware upgrades and super-fast charging. Now it’s true, the screen is a bit boring if you compare it with their new Sigelei MT 220W Mod but that aside it’s perfectly laid out and easy to read/use.


Tank It Up

Since the 510-connector can manage atomizers with a diameter up to 32mm, you’ll have no problem matching it to your favorite tank. The Digiflavor Pilgrim GTA or OBS Crius RDTA will work well, and because the pin is centered, they will look brilliant. However, you might pause before using very large tanks like the SMOK TFV12 Cloud Beast King or the Wismec Reux Tank on the dual battery configuration. They’ll fit, and the mod can handle very low resistance coils, so you’ll get a great vape, but you’ll need to take some care when putting the mod down. A huge tank on the slender duo config can be top heavy, and you may prefer the trio-battery config for that.

Blue version of the Sigelei Fuchai Duo-3

Temperature Technology

Sigelei’s chipset technology is excellent and is also fully upgradeable. The same microprocessor handles both versions (it’s the same mod, just different battery cases as I mentioned before). The duo config can fire up to 175W while the trio config can handle 225W.

Choose this mod for its precise temperature control, the sophisticated power pre-heating function, and Sigelei’s temperature compensation system which monitors and adjusts the temperature automatically. This is one of the best vape mods in its class without a doubt.

The Sigelei Fuchai Duo-3 handles from 0.1 to 3 Ohm atomizers and has TCR and TFR functionality, so users can adapt the mod to any vaping style using Nickel, Stainless Steel, Titanium or Kantal coils. You have the option to add some serious Watts if you choose the 3-battery config, but vaping at 100+W with two 18650 batteries will get some awesome clouds. If you usually chug along at 50-80W, you’ll have no problem with battery life.


Versatile Battery Body

You secure the set of two Li-Ion 18650 batteries with a back-mounted clip-on battery case – which must lock securely into a small slot on the chassis before the mod will fire. We have heard isolated reports that some units have a little play on the slot and do not lock down securely the first time. The 3-battery config battery case operates on the same principle.

The packet with the Sigelei Fuchai Duo-3


  • 510-threaded and centered pin allows use of favorite atomizers up to 32mm diameter
  • Slimline and low weight, with the option of adding bulk (extra battery) when you use huge atomizers
  • Variable Wattage: 10.0 – 175W or add an extra battery and go up to 255W
  • Sigelei’s popular preheat functionality and temperature compensation controllers
  • Use with any coil you want
  • Bright color display screen with easy to read operating interface



The Sigelei Fuchai Duo-3 175W is a welcome addition to the growing number of mid- to high-wattage mods. It has excellent temperature control, a low weight and small size, but plenty of features, and – impressively – is earning a reputation for producing no misfires at high wattages. It is well built, sleek and can manage any vaping style with no trouble making Sigelei one of the best vape manufacturers around. It is reasonably priced and will go down a treat with anyone moving on from a vape pen up to advanced mod users. Good one, Sigelei!


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Nicholas King
Nicholas King

Hi! I’m Nicholas King, the founder, and Chief Editor at SmokeTastic. As an ex-smoker and now vaping enthusiast for over 13 years myself, I understand the transition between smoking and vaping. My aim is to share useful information about all the different vape and e-cig products on the market, self-help tips, and detailed reviews.

I hope you find something on SmokeTastic that helps you with your decision process.

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