G Pen Pro Review l Herbalize Blog

G Pen Pro Review

July 28, 2018

G Pen Pro Review

G Pen Pro Review

The G Pen Pro is a solid, compact and affordable portable vaporizer that gives a tasty vape and a long battery life. This G Pen Pro review hopes to separate fact from fiction and make it easy for readers to choose the right vaporizer for them.


Grenco Science is a relative newcomer to the world of portable vaporizers but has quickly gained a very positive reputation for well designed, high value devices. Endorsements from celebrities such as Snoop Dogg, DGK and others have added to the esteem of the company and ensured a meteoric rise to the top tiers of vaping technology. They offer a range of devices covering all vapour bases. The G Pen Pro was released in 2014 and has seen upgrades since. Designed specifically as a dried herb vaporizer that can handle session use and extended periods of vaping. For a relatively low price tag of $99.95, the G Pen Pro is nestled in the affordable end of quality portable vaporizers.


  • What is in the Box?
  • Upon opening the sleek and elegant cylindrical G Pen Pro cardboard tube, there is found:

    • one G Pen Pro,
    • a micro USB charger,
    • a G Pen Tool, and
    • a cleaning brush

    G Pen Pro Review


    The G Pen Pro is very well presented: the packaging feels good to unwrap and adds to the experience of using the vaporizer for the first time. It is a solid indication of quality from Genco Science.


    First Impressions

    The first impressions of the G Pen Pro are very positive, with its satisfying weight and smooth coated stainless steel case giving a good impression of quality. After charging, the Pro was ready to use and performed well from the first hit. The chamber packed easily and was big enough for sharing, there was minimal pull resistance through the unit, and the vapour was tasty.

    G Pen Pro Review

    The cylindrical unit is black and sleek, with a rubber mouthpiece at one end and a rubber cap over the heating chamber at the other. There are 4 LED lights on the front that display the charge status, flashing in sequence when charging and all 4 turning on when it is fully charged. When a different temperature level is chosen by pressing the button in the centre of the Pro, the LED lights flash red, blue or green.

    G Pen Pro Review

    The G Pen Pro is small enough to fit in a pocket discreetly but not small enough to fumble. It is a very ergonomic device with a well-placed button and a comfortable mouthpiece.

    G Pen Pro Functions

    This portable vaporizer can pack in up to 0.25g of dried herbs in the easy to access herb chamber. It can vaporize dried herbs but will not function well with concentrates or extracts.

    G Pen Pro Review

    Using the G Pen Pro

    To turn on, press the button five times and wait roughly 30 seconds until the LED lights are a solid colour.

    G Pen Pro Review

    The heating element takes around 30 seconds to reach the desired temperature. There are 3 presets to choose from: red, blue and green. Blue is the lowest temperature at 375°F (190.5°C), green is 400°F (205°C) and the hottest is red, at 428°F (220°C). Hold the button to select the temperature and wait until the four lights on the front have stopped flashing.

    Battery Life

    The G Pen Pro has a 2200mAh lithium ion battery that will last for up to 40 minutes of continual use, or several days’ vaping for a heavy user. Combined with the decent sized herb chamber, it is a usefully long lasting device that can also be used in social situations.

    There is a 4 minute auto shut off to save power when no input is detected.


    The Pro uses a micro USB charger that comes included, but any will do. This is useful as it will charge anywhere a phone will as micro USB is ubiquitous.

    The charge time for the G Pen Pro is roughly 2 to 3 hours for the first charge and about 2 hours from then on.


    At 116mm tall and with a diameter of 25mm, the Pro is not the smallest portable vaporizer on the market but it is well designed and sized. It fits nicely into the palm of the hand and can be slipped into a pocket unnoticed for maximum discretion.


    The mouthpiece is made from PBT, a plastic with a melting point of around 240°C. This does not cool the vapor as well as glass mouthpieces might and has questionable health credentials. It is, however, tough, and durable, perfect for sitting in a pocket with a bunch of keys and not breaking.

    The body is made from tough plastic and steel and appears to be well constructed.


    The three presets, blue (375°F/190.5°C), green (400°F/205°C) and red, at (428°F/220°C) offer a decent temperature range that will cover most vaper’s uses. The accuracy is not the best but it gives a roughly consistent vape.

    Vapor Quality

    The vapor from the G Pen Pro vaporizer is not as dense as some vaporizers in this range but is very flavorsome. Thick vapor is hard to achieve in a portable device, and the Pen Elite offered by Grenco Science offers a superior vaping experience.

    There is a slight burnt popcorn flavor at the higher temperature setting that could put some users off, however it is not the dominant flavor and the experience is still enjoyable. Regular stirring of the dried herbs is essential during a session, which can be a little tedious, especially during a long session.

    While the desired temperature is reached in about 30 seconds, if it is left for a further 30 to 60 seconds, better vapor production is achieved. It can take a few deep draws to get an achievable and tangible vapor experience. An over-packed chamber will result in a difficult draw and uneven vapor production.

    The G Pen Pro has a low draw resistance, much better than some of the competitors on the market. This is combined with the lacklustre draws, so it is a compromise. Low draw resistance but relatively thin vapor.

    The highest setting is generally the most enjoyable, however all three are of acceptable quality, especially considering the sub 100 dollars price tag.


    This device is designed specifically for dried herbs and will not work with concentrates, waxes or oils. There are not currently available any add-ons that will give this capability, so users who want to use concentrates or both herbs and oils should look elsewhere.


    The rubber mouthpiece and end cap can be removed and cleaned using the cleaning tool that comes in the box for the G Pen Pro. The chamber will need cleaning every dozen or so uses and will clear out easily using the pipe cleaner that is included. Generally, it is a very low maintenance device.

    G Pen Pro Review

    Heating Element

    The heating element is ceramic and heats by conduction.


    For under $100, there are not many vapes of this capability on the market. It offers a long battery life, pretty good vapor and acceptable construction qualities and materials. It presents a high value deal for discreet session users.

    Design and Construction

    Designed in California, made in China, the quality suffers a little from the evident cost saving process designed to get it under $100.


    For a vaporizer with the capabilities it has, the G Pen Pro is very discreet, with a small cylindrical design and a smooth finish, enabling quick access and hiding if needs be. For use in public places or high risk situations, or just for someone who wishes not to be seen vaping, the G Pen Pro is one of the best small portable vaporizers on the market in terms of discretion against capability.

    G Pen Pro Review

  • Conclusion
  • The G Pen Pro is faced with stiff competition from other producers on the market, with a number of devices in this price range offering a similar quality and material build. The vapor is not the thickest but is amongst the tastiest in the price range, even with that slight burnt popcorn element added in.

    For users of concentrates, this is not the device for them. It is only for dried herbs and does a decent job of it. The real pros of the device are its extended battery life and low draw resistance. Marketed as a device for session use, it can handle 40 minutes plus of pure vaping, and is a very socially utilized device, offering a comfortable and easy to use vaping experience.

    The temperature flexibility is useful but not as broad as a few other portable vaporizers, though none for under $100. The three settings offer a pleasing combination of effects and can get a decent flavor and vapor from most dry herb mixes. This is not a connoisseur’s vaporizer, it will not get the best out of high quality herbs, but it will get a very good result regardless. For those willing to spend a little more, the Elite offered by Grenco Science is more up their street.

    In terms of flavors, the quality can drop off relatively quickly during a session. This is not a device to eke every last drop of vapor from a herb mix; it is one for a few quick sessions and a sociable pass-round for everybody to enjoy discreetly.

    An interesting compromise of a device, it offers decent quality for a very decent price and should be included in any list of sub 100 dollar portable dry herb vaporizers. While assembling this G Pen Pro review, it was evaluated and reviewed extensively, relying on testimony and experience to provide the clearest picture of the device possible.

    G pen pro vaporizer review


    Shop G Pen Pro

    This G Pen Pro review has given it a high value rating, meaning it has some small deficits but is a definite contender for the money.



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