Description
Gansulin Automatic Pen is a green, spring-driven reusable pen sold by Daro Pep for compatible 3 mL cartridges. The current catalog specification provides 1-unit settings up to 60 units, audible operating clicks, and a remaining-volume stop. This listing includes the pen and its travel case; cartridge, needle, and liquid are not included.
Gansulin and the ServoPen platform
Ypsomed’s corporate history identifies the Gansulin pen as the first product launched on its ServoPen platform. That source establishes the platform lineage, but it does not make Gansulin and Convipen identical products. Tonghua Dongbao’s official product listing identifies Gansulin and describes a 3 mL, 300-unit format.
After an amount is selected, the spring-driven mechanism completes its operating stroke when the button is pressed. Daro Pep classifies the pen as fully depleting when fewer than 2 units remain. This threshold describes the store’s comparison method and does not mean an absolute zero remainder.
Daro Pep lists the Munan sterilized and siliconized 3 mL cartridges as a compatible pairing that does not require an adapter in this pen. Other cartridges and needles can differ in dimensions and tolerances even when described with similar terms, so compatibility should be verified for the exact combination.
Gansulin pen specifications
| Operation | Automatic, spring-driven |
|---|---|
| Manufacturer | Tonghua Dongbao Pharmaceutical Co., Ltd. |
| Platform lineage | Ypsomed ServoPen |
| Setting increment | 1 unit |
| Maximum setting | 60 units |
| Cartridge format | Compatible 3 mL cartridges |
| Daro Pep-listed cartridge pairing | Munan 3 mL cartridges |
| Adapter needed with that pairing | ✖ No |
| Remaining-volume stop | ✔ Yes |
| Daro Pep depletion classification | Fewer than 2 units remain |
| Operating feedback | Audible clicks |
| Digital memory, Bluetooth, or NFC | ✖ None |
| Color | Green |
| Travel case | ✔ Included |
What is included
This listing includes one green Gansulin pen and its travel case. A cartridge, needle, and liquid are not included. Cosmetic options are available in the pen covers and accessories collection.
📘 Platform reference only: View the generic ServoPen reference IFU (PDF). This document is a generic template, not a Gansulin-branded manufacturer manual, and it does not replace product-specific compatibility information.
Gansulin compared with Convipen
Gansulin and Convipen have similar cataloged controls and setting ranges, but they are separate products. Gansulin is green, has documented ServoPen platform lineage, and includes a travel case. Convipen is blue and ships as a bare pen. Review the complete pen comparison before choosing between them.
Gansulin FAQ
Is Gansulin the same product as Convipen?
No. The two listings share several specifications, but the available evidence does not support calling them identical.
Is Gansulin the same as GensuPen or Gensulin?
No. Gansulin is the product covered on this page. GensuPen and Gensulin are similar-looking names associated with other products and should not be used interchangeably in descriptions, searches, or structured data.
Which cartridges fit?
Daro Pep lists its Munan 3 mL cartridges as a compatible pairing. Compatibility with every cartridge marketed as 3 mL should not be assumed.
Does the listing include a case?
Yes. The green Gansulin pen and a travel case are included. The cartridge, needle, and liquid are separate.
Official sources
All products sold by Daro Pep Accessories are strictly for research purposes only and are not intended for human or animal consumption.






Cody I. (verified owner) –
The best pen I own along with the Convipen! Spot on every time and makes injecting so much easier!
David B. (verified owner) –
Was my entry into using pens and is still my favorite. Accurate and easy to use.
Emmett (verified owner) –
The Gansulin is a great auto-pen. It’s accurate and dispenses quickly! The green color of it is vibrant as well.
Michael P. (verified owner) –
Stumbled across Daropep and saw the price on this Gansulin and pulled the trigger immediately. Everywhere else I had seen them they were double this and I figured I had nothing to lose. Got it in and double checked it, its authentic, works great, and he has it for the best price your going to see it. Great option if youre looking for an autopen.
Brandon L. (verified owner) –
The Gansulin pen I got from Daro is by far, one of the best pens I’ve ever owned. Consistent dosing, super smooth movement, easy button trigger. Absolutely love the auto-injection mechanism because it saves jerky presses on my part where other pens were just plain trash. Would 100% buy more when I need another pen. Between the Gansulin pen and the Convipen, you can’t do any better.
Alfred B. –
First pen. Shipping was fast, I immediately ordered more pens to try. I’m hooked on them. I did some basic non scientific testing on dosing and it is accurate and very easy to use. Didn’t take long to figure everything out. Now using it daily and so far my favorite. Will be ordering regularly from DaroPep!
Nicole D. –
What a difference from a V2 or V3. The quickness of delivery is superb. Little tighter to get to your units but just a sled of the button to deliver quickly. I use it with GHK-cu and there is no pain at all. No more welts! Would but it again in a heartbeat!
godoyallan89 (verified owner) –
Very sturdy and accurate pen. Found it to be slightly better than the Convi pens I have.
Kris M. (verified owner) –
I love this pen, sleek and effective. Super fast shipping too. Is it wrong for me to wish the case was plain and a bit more discreet? Nothing taking away from this amazing pen, just something I noticed.
Jason (verified owner) –
The Gansulin is a good pen. If you are interested in trying an auto ejector, you really can’t go wrong with it. I would recommend it. However, the Convipen is slightly less expensive and almost identical in quality. The Gansulin may be slightly easier/smoother to dial your dose but the difference is negligible. The pen is supposed to not let you dial more units than what is left in the cartridge, but according to my testing it was not accurate. Let’s say the pen only lets you dial it to 50 units; you may only get about 35 units with the injection. The same applies to the Convipen and Savvio pens, which are the other two with this feature that I’ve tested. Just keep that in mind.
Jason (verified owner) –
Just to clarify, the accuracy issue is only with that final dose based on the number of units the pen lets you dial. Otherwise, the Gansulin pen was always accurate in my tests. Sorry, I couldn’t edit my previous review.