Reinventing a good thing is not such a bad idea especially when you can improve upon it, and at first glance, it appears that Innokin has achieved just that with the latest upgrade to the popular CoolFire IV-one of my hot picks for 2015 when it was first released some months back.

The Coolfire IV Plus as the name suggests has a few added improvements with an increase in battery size up to 3300mAh to make it an even more, attractive option for the Sub Ohm vaper with combined output power from 6W all the way up to its maximum of 70 watts.

They have also included the iSub G tank into the package making this a very attractive kit and with their outstanding ability to design something that not only looks good but is reliable and safe to vape you can expect to see the CoolFire IV Plus being vaped around town wherever you are.

I took some time out yesterday to visit some of the increasing numbers of Vape Stores and Vape Cafés here in London with it, which proved to be a hit with both them and their customers, who liked its size, weight, screen size, and overall general appearance. This was useful feedback for me, prior to writing this review.

Innokin has provided four colour choices in Black, Red, Silver, and Blue combined with a choice of Black and Stainless iSub G’s so you should find something to suit your personal taste.

Innokin sent me the iSub G kit. However, they now appear to be including the iSub APEX tank with their Coolfire IV Plus kits so please be aware of this if and when you decide to purchase one for yourselves.

So what’s in the box and how much will it cost you?


Tastefully packaged, the Coolfire IV Plus Kit shows on the outside what you can expect to see on the inside. Quality!

Remove the outer shrink wrapping along with the decorative cardboard sleeve that gives you some introductory information about the device plus a scratch and check security code sticker on the side to verify that this is an Authentic Innokin product.

On the base of the box you will find further information about the contents and performance that is worth reading, but for now, lift off the lid where you will find your device, tank, and a spare coil. Notice there is a small black tab at the bottom. Lifting this up gives you access under the protective foam to the charging cable and user manual with an additional information card on how to use your iSub G/Apex. And, finally, an Innokin sticker to help verify that this is a genuine product and not a cloned version.

What’s new

6W-70 Watts of Real Vaping Power
Battery Dimensions:3-3/8″ x 1-7/8″ x 1″
Spring loaded, gold plated positive pin
High-Quality Stainless Steel 510 Thread
3 Click Lock-Unlock Feature
Large, Bright OLED Screen
Comfortable Firing Button
Vape While Charging
Vrms power regulation
Tri-colour LED Battery Level Indicator
15 Second Cut-off Timer
Advanced onboard safety features
Automatic real-time atomizer Ohms detection
Overheat and Over discharge Protections
Fires coil resistances from 0.1 Ohm to 3.5 Ohm
Operating Voltage: 2.0V – 7.5V
Operating Wattage: 6.0W – 70.0W
Built-In 3300mAh battery
Standby current: 100uA max
Maximum output Wattage: 70W
Maximum output Current:26.5A
Maximum output Voltage: 7.5V
Charging: Micro USB DC 5V/1A
Comes with a 90 Day Limited Warranty

Innokins Battery Safety Recommendations

Do not leave the battery unattended while charging.
Never charge a battery that has been damaged or dropped. 
Never plug a charger into a non-approved mains power transformer.
Do not overcharge.
Remove the battery from the charger when complete. 
Never leave a charging battery unattended. 
Only use the included high-quality charging cable. 
Wall Adapters should be CE / UL/ FCC certified, high quality and authentic. 
Do not charge your vaporizer with your car charger.
Supports 5V/2A fast charging

Function & Performance

I have tested the CoolFire IV Plus’s full range, from 6 watts all the way up to its maximum of 70 watts. I have also used the enclosed iSub G plus the iSub Apex tanks, along with the Steam Crave 6ml RBTA in combination with varying PG/VG combinations from Five Fold Vapor and Dark Market.
For customers within the UK, these E-Liquid lines can now be purchased online.

REACH compliant

If you intend to use this range of E-Liquids, please make sure they meet the current requirements set out by your countries regulatory bodies.
For EU countries, more information on this can be found here along with REACH’s partner agencies from around the globe.

E-Liquids may contain Diacetyl (DA) and Acetyl Propionyl (AP) or other carcinogenic ingredients or disease-causing substances, so please be aware of this and seek medical advice before using any of the products used in my reviews.

People can suffer from allergies to chemicals that may be present in the makeup of certain types of E-liquids or produced in their vapour. People can become sensitive to, or even allergic to Nickel or Titanium used in Temperature Controlled designed coils. Again, please be aware of this and seek medical advice before using any of the products used in these reviews. You can also check with your E-liquid supplier or the equipment manufacturers directly prior to purchasing.


Here is a quick start up guide on how to use your new device. For a more detailed description, please consult the enclosed user manual or the link provided for you at the end of this review.

One of the most important things for new users is to remember is not only to fill up your tank with E-liquid but, most importantly, soak the organic cotton coil with E-Liquid as well.

This will prevent a burnt taste (dry burning) when you fire your device for the first time. Innokin recommends leaving the juice to soak in for around five minutes before use. Reattach the tank to the device via the High compatibility 510 connector (not too tightly) and you’re ready to go.

Powering up the Coolfire IV Plus requires only three presses of the fire button (situated above the OLED screen) in quick succession to start vaping. You will have noticed a LED surrounding the fire button which is a Tri-Colour LED Battery Level Indicator. This displays the current status of your battery using three colours.

Green equates to a full charge, Amber half charge, and Red which indicates that the battery requires you to recharge it using the supplied cable.

The Red LED and Battery Bar will continue blinking when the battery capacity is lower than 3.3V, and the device will automatically power off.

The Coolfire IV Plus is a Variable Voltage (VV) Variable Wattage device and has no temperature control functionality built in so be sure to purchase the correct coils to use with either the iSub G or Apex tanks. These coils are also interchangeable between both. Your local E-Cig store should be able to advise you on this subject so check with them when purchasing the CoolFire IV Plus as a kit.

Variable Voltage can be adjusted from 2.0 – 7.5 volts in .1 volt increments and Variable Wattage can be adjusted from 6.0 – 70.0 Watts in .5 watts increments.
To switch between these two modes of operation press the Power button together with either the Plus + or Minus – buttons.

You also have the option to rotate the screen by 180 degrees to suit your personal orientation depending on whether you are left or right handed. To change it hold down both the Plus + and Minus – buttons at the same time.

Safety while vaping is of great importance as we know, especially for newcomers to vaping. Innokin products are renowned worldwide for being one of the best Companies in providing high levels of safety features in their products and the Coolfire IV is no exception.

These include

3x Click Lock-Unlock Feature:
A simple and efficient way to turn the device on or off.

The Innokin Coolfire 4 Plus also features automatic real-time atomizer Ohms detection. If the resistance of the atomizer is lower than 0.1 the Ohms bar will blink and the Innokin Coolfire 4 Plus will not power on.

Remembers last Voltage or Wattage settings

When the Innokin Coolfire 4 is turned off it will remember the current voltage or wattage setting and it will retain the setting when the Innokin iTaste Coolfire 4 Plus is powered on.

Short Circuit/Atomizer Protection:
Short Circuit/Atomizer Protection protects the device against shorted atomizers and will stop the unit from functioning in unsafe conditions.
Over-Discharge Protection

The Innokin Coolfire 4 Plus monitors the battery voltage and will automatically power off if the battery is over discharged.

15 Second Cut-off Timer

If the power button is held down for up to a maximum of fifteen seconds continually the device will shut down to protect you from the possibility of the battery overheating and venting.

Vape while charging” Technology:

The Innokin Coolfire 4 Plus is recharged with a Micro USB cable. When plugged into a power source the Innokin Coolfire 4 Plus can also be used and charged at the same time with Innokin Technology’s Vape while you charge pass-through technology.


Innokin has made some useful changes to an already well designed and specked device that should help the CoolFire range keep up with the ever-increasing demand for sub-Ohm vapers who require more output power and increased battery performance on a daily basis.

Coupled with a well-designed iSub G tank and recognised as one of the best Companies to provide reliable technically advanced VV/VW devices, that is backed up with by performance and excellent safety features, this should help to make this version one of the very best in its class for the start of 2016.

Innokin appears to have included their Apex tank which I believe will replace the iSub G in this kit so take this into account when making a purchase. Either way, you can expect a flavoursome vape thanks to the Japanese organic cotton coils and extremely good cloud production too.

Easy to operate, ergonomically designed, and with a solid connection on all atomizers used in this review, thanks to the gold plated centre pin which should provide ample air flow no matter what type of tank is attached to it. You will notice that the engineers have paid particular attention to the detail in this area by placing a juice well around the outside.

Buttons are both tactile and well positioned requiring only a small amount of pressure to activate them with a very soft click as an audible reminder that they have been activated.

Operational information along with menu structures is provided by way of a large clear bright OLED screen that is easy to read and navigate around just like the device itself. Made to stand up to the rigors of daily life, while providing the user both old and new with an uncomplicated vaping experience, in a very comfortable package.

You will notice a small increase in weight compared with its predecessor, but nothing that is in any way uncomfortable to hold for extended periods of time. The venting holes are placed on the right-hand side of the device both top and bottom providing what appears to be sufficient room for gases to escape in the unlikely event of your battery overheating, and for providing  additional air circulation cooling the battery and internal circuitry. There appears to be room on the base of the device for further vent holes to be added which is a small point but worth mentioning.

The micro USB port is nicely situated on the front and I have given this a fairly thorough test to see if the connector (female) withstands plenty of use without breaking. So far so good!

Some people have complained in the past that they have broken this part of the device rendering it useless. Always check that both ends marry up correctly before inserting the cable into the micro USB socket and push in with a gentle straightforward motion avoiding any unnecessary side to side movements. This I hope will help you avoid any such problems in the future. And remember; make sure you always purchase a genuine product and not a cloned version. They may be cheaper in the short term….

Personally, I have not come across this problem with any vaping devices that I have been sent for review to date irrespective of the manufacturer, so I hope this tip will help you to avoid this happening again if you have been unlucky enough to have experienced it and get the most from your Coolfire IV Plus.

Vape while charging is also included so thanks to this and the excellent build quality you should in theory never be without a vape.

And if Temperature Controlled devices are what you are looking for then Innokin have this covered too with the release of yet another new product. Stay tuned!


Expected price range appears to be around the £59.00 or $74.00 mark.

All products are sent directly by the manufacturer for review

For further details on the CoolFire IV Plus or any other Innokin product, please visit the Innokin website or contact your local brick and mortar store.

To View The User Manual: Click  Here

Thanks to Innokin for providing the Technical specifications for this review and Images of the CoolFire IV Plus from their website.


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