Jes Extender Review and Clinical Studies

Jes Extender is a penis enlargement device which has been on the market for more than 20 years. This device was originally designed for Peyronie’s disease, a condition characterized by the irregular curving of the penis.

The Jes Extender is the oldest among modern penile extenders. It got its name from Jes Bech Mueller, the founder and CEO of Denmark-based manufacturer DanaMedic ApS, the manufacturer of Jes Extender. In 1994, Mueller collaborated with Danish surgeon Jorn Ege Siana to develop this device.

DanaMedic also makes other penile extenders. There is the SizeGenetics (read our SizeGenetics review here), which looks the same as Jes Extender, and the MaleEdge, a second-generation penile extender introduced in 2008.

Visit the Official Website of DanaMedic for the latest accurate prices.

Jes Extender has the European CE mark as a Class 1 medical-grade device, making it safe for home use. In Australia, it’s the only penile enlargement device approved by the TGA (Therapeutic Goods Administration).[1] DanaMedic stated that Jes has a registration with the U.S. FDA (Food and Drug Administration).[2]


According to DanaMedic, the Jes Extender offer the following benefits:

  • It can increase the length and girth of your penis by up to 28%, without resorting to surgery. More than 100,000 users have been satisfied with the Jes Extender.
  • There is a broad range of tensions that can be applied during extension activity. The typical range is 900 to 1,500 grams, but the maximum limit is 4,000 grams.
  • The first sign of penis growth can be seen within seven days of usage.
  • Aside from size gains, Jes Extender can also correct penis curvature, particularly that of Peyronie’s disease.
  • The Jes Extender has been clinically tested, and several studies have been posted on their website.[3]

Customer Reviews

Here are customer reviews that were submitted by Jes Extender users. Click the button below to submit your own review.

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Penis results


I have logged over 500 hours with the Extender and have gone from 7x5.5 to 9x5.5 and am very pleased with the results. I have bought additional rods for future growth. The last girl I slept with couldn't believe my size.

Erection Issue


I recently bought the Jes Extender, hoping I could add half an inch to my 6”x5” penis. Well, I guess I hoped too much.

As recommended, I started slow, only one hour on the first day. I steadily increased the number of hours until the third day. The tension I used never exceeded 900 grams.

On the fourth day, everything seems normal. But at the back of my mind, I was thinking that I’m not getting the usual boner when I wake up. For the rest of that day, it was difficult for me to maintain my erection, plus it doesn’t happen spontaneously. I reckon that this is due to overworking my penis and the constant worrying when the penis is not in its normal mode.



My flaccid penis is now over an inch longer, and its head is bigger as well. The one complaint that I have is that it is so hard to wear the extender day-in and day-out. Jes Extender undoubtedly works, but you must have the commitment to make it effective.

No success


I disapprove this. I initially thought gentle stretching for long periods of time will do wonders for my penis. Unfortunately, I had no success so I am back to doing manual exercises. Right now, I am considering doing pumps.

Nobody will notice you wearing it


This is my first review. I have some good and some bad things to say about them. First, they are effective. I have an erection length of 6.25” and, after 3 months, it is now at 6.75”. The downside though is that you need to wear this thing a lot.

I disagree though that it will look obvious that you’re wearing this extender. As long as you wear loose pants, no one will notice. Unless someone is looking at your crotch.

Jes Extender rated 3.4/5 based on 29 reviews.

How does it work

The Jes Extender promote a painless, non-surgical way of penis enlargement through the process of traction.

Simply put, traction is stretching. By subjecting a flaccid penis to a steady, gentle dose of stretching, Jes Extender takes advantage of the body tissues’ ability to grow under stress. Setting the tension between 900 to 1,500 grams force will stretch your penis beyond its current length.

Over time, the cells will divide and multiply as a response to continuous stress. This natural process is called cytokinesis. As a result, cells multiply and the tissue grows in size, which is then manifested as an increase in penis size. While gains happen mostly in length, there is also an increase in girth as well.

Traction is not a new process, and it’s the same mechanism the body uses for broken bones and grafted skins.


Jes Extender is made up of four units:

  • A ring that fits the base of the penis.
  • Two spring-loaded bars that are connected to the base ring. The length of the bars can be adjusted depending on your preferred tension.
  • A front piece that will support the glans (the head of the penis). Once the glans has been secured into place, it holds the penis in a still position while the actual extension is happening. Depending on the package, there are several options for strapping the glans into the front piece. The comfort strap and the silicone tube for the traditional noose style are available in all packages; the Gold and Platinum Packages has a velcro strap.
  • Additional elongation bars. Depending on the package, these parts are included to accommodate your current penis length and desired size.

How to Use


After assembling the Jes Extender, here are the steps to use it:

  1. Place your flaccid penis through the base ring and within the two elongation bars.
  2. Let the head of your penis rest on the front piece. Securely strap the head.
  3. Twist the elongation bars to apply traction. This will adjust the length of the device. The traction should not be too tight (it could cause harm) or too loose (you won’t gain any growth).

For full instructions, check the included manual.

Sample Routine

For starters, here is a sample routine:

Period Recommended Traction Number of Hours Daily
Week 1 to 3 900 grams 1 to 4
Week 4 to 6 1200 grams 4 to 6
Week 6 onwards 1500 grams 6 to 12

The above routine is for guidance only. Once you hit a certain level of comfort, you can change the way you use the Jes Extender. You can use it 4 to 6 times a week and don’t exceed 12 hours of usage per day.

Remember that, like any penile exercises and other penile enlargement tools, it’s best to start slow until you get accustomed to using the extender. Your extension activity must be seen as a marathon, not as a sprint.

Frequent Use

Once you get the hang of it, you can now wear Jes as you like, not only during your free time. You can wear it with loose clothing, without anyone noticing you are actually wearing it. You can wear it to work, as long as your job is not physically demanding. You can even wear it while sleeping, as long as you don’t turn a lot or as long as you remain lying on your back.


  • The Jes Extender can be easily set up, and it’s easy to use.
  • Comfort varies per user, but generally, there is no long-term comfort issue with the Jes Extender. Depending on the package, you will get access to various accessories, like comfort strap, velcro support, protection pad, and gauze.
  • You can choose and adjust the tension, depending on your goal and comfort level.
  • The Jes Extender is discreetly packaged upon delivery.
  • If you are don’t get the expected benefits within 1,000 hours of usage, DanaMedic offers a 200% refund within a year of using the product.
  • The extender can accommodate penises of different sizes and will work regardless if you’re circumcised or not.
  • Unlike surgeries and medications, the Jes Extender has no side effects, provided that the device is used properly.
  • Jes Extender is made from high-quality materials. The cheaper packages have stainless steel rods while the more expensive ones boast of gold-plated or platinum-plated materials. Other parts of the extender are made from medical-grade, hypoallergenic materials.


  • While the Jes Extender is generally comfortable, it is not uncommon for first-time users to experience discomfort. It is recommended to use the protection pad and other comfort accessories included in the package.
  • The Jes Extender is not available in local stores and can only be purchased online.
  • You can’t urinate, masturbate or have sex while the Jes Extender is on. If you’re the type of guy who always goes to the toilet, it is going to be unhandy to remove the device frequently.
  • Results vary per person. Depending on many factors like age, physical condition, genetics, traction used, and the frequency of use, the degree of size increase is not uniform.
  • Results take time to be visible. While the manufacturer claims results are seen in the first seven days, it will take months before you achieve your desired size. After all, growth will not happen overnight.
  • While Jes Extender has been shown to be effective, its design is already dated. One common complaint with the design is that the single strap is a constant source of slippage and readjustment.
  • The device is expensive. There are other penile extenders out there that are cheaper and more versatile.

Where to buy

You can buy the Jes Extender at its official website Depending on your needs and budget, there are six options you can choose from: Light, Original, Titanium, Silver, Gold, and Platinum.

Common Features

All packages have these common features:

  • 1 Base ring, 1 Silicone Tube, 1 Comfort Strap, 1 Protection Pad, and 1 Instructional DVD.
  • 2 Spring-loaded bars: These are attached to the biologically contoured base ring. These parts can be adjusted from 0 to 1500 grams traction, with 800-1200-1500 indication markers. Packages have different types of coatings.
  • 1 Dual function front piece: This support is compatible with the soft comfort strap, velcro strap, or the silicone tube for a traditional noose style.
  • 2 additional elongation bars 1”/2.5cm: Like the spring-loaded bars, the material of construction also depends on the package.

Unique Features

Here are the other features of the packages:

Characteristics Jes Extender Light Jes Extender Original Jes Extender Titanium Jes Extender Silver Jes Extender Gold Jes Extender Platinum
Box Cardboard Mahogany Aluminum Fightbox Mahogany Mahogany Lacquer finish wood case
Bar Coating Stainless steel Stainless steel Stainless steel Silver-coated Gold-plated Platinum-coated
2”/5cm elongation bars 2 4 4 4 4 4
Set of tightening keys No 2 2 2 2 2
0.5”/1.25cm elongation bars No No 2 2 2 2
Cohesive gauze No No No 1 1 1
Softattach No No No 1 1 1
Velcro strap No No No No 1 1
Warranty 1 year 2 years 2 years 5 years Lifetime Lifetime
Price (shipping fee excluded) €179 €199 €219 €249 €299 €1,000
Starting Penis Size Up to 17cm (7”) Up to 24cm (9”) Up to 25cm (10”) Up to 25cm (10”) Up to 25cm (10”) Up to 25cm (10”)


The shipping fee is €15. Delivery takes 1-3 days in EU, and 2-5 days in the US, Canada, and the Pacific region.

Scientific Studies

Four studies have been cited by DanaMedic on its website, showing the effect of penile extenders on penis size and curvature. However, it is not explicitly stated that Jas Extender was the actual extender used in these studies.

  • In 1998, Dr. Siana, Jes extender co-developer, reported a 28% increase in penis size in ten patients who undergone penile traction therapy at Barcelona-held 1st International Interdisciplinary Symposium on Genitourinary Reconstructive Surgery in Congenital Malformations, Transsexuals, and Impotence. That trial lasted for 24 weeks.[4]
  • A comparative study made by two doctors from the University of Turin, Marco Oderda and Paolo Gontero, was published in the April 2011 edition of the British Journal of Urology. The main point of the paper is that, among penis enlargement techniques, “penile extenders represent the only evidence-based technique of penile elongation.[5]
  • In an independent study conducted by urologist Wendy Hurn on 22 men diagnosed with Peyronie’s disease, it was shown that penis traction could reduce penile curvature by 20%. In addition, an increase in penis length that ranges from 0.8 to 0.23 cm was also reported.[6]
  • Another study conducted on 26 males with Peyronie’s disease has shown that, after six months of penile traction therapy, the average curvature is reduced from 49.8º to 28.7º. The average length also increased by 3.3 cm in flaccid penises and 2.1 cm in erect ones.[7]

Results and Recommendation

As one of the original penis enlargers on the market, there’s a reason why Jes Extender stayed relevant even with the arrival of supplements and other penile enhancement products. The Jes Extender can lead to size gains with zero side effects, as long as the product is used properly. The only issue is that there is initial discomfort for first-time users.

If you’re the type of person that will quit from frustration after using the extender for a week, then this device is not for you. Results vary between users, but generally, three months is what you’ll need to really notice some size increase. Extend your usage to six months to attain the full potential of this device. We have heard of users extending the usage beyond six months; surprisingly, their penises still register some growth.

For patients who underwent a penile surgery, they also can benefit from the Jes Extender. Penis retraction is common after such procedure so an extender can help regain original penis size, even gain some more. It’s strongly recommended though to recover first before attempting to use the Jes Extender.

As we mentioned in the “How to Use” section, it is important to start slow. Once you become comfortable with the device, you can now use it for 12 hours, for at least six months. Consistency is the key, so you must use the device regularly.

In the end, the good thing with the Jes Extender is that you can choose when to use it, apply the precise traction that meets your needs, and stop once you already attained your goal.

More Customer Reviews

As customer reviews get older with time, they scroll all the way down to this section.

There is gain but not that big


In my case, the Jes Extender did work. After six months, I gained 0.5 inch in erect length. I have been taking some medications lately so my erection and libido is a bit low. Otherwise, there could be an extra length in there. But I have no worries, I will still continue to use it.

For me, this is a nice gain already. Just don’t expect two inches or more after 6 months of wearing it.

Just wear it


I read about pills, creams, and patches, and they all sound crap to me. No, I have not used any of them, but I still think they’re just a waste of money. I also thought that jelqing and penile exercises are also crap, but I discovered they do work.

Then, I stumbled upon extenders and how to use them. Put your penis under traction, then it grows bigger. If you look what happens to guys who have those circular things in their earlobes, it is the same case with extenders. Just put it on, that’s it. It’s good when you just free time at home, in front of the TV or computer. Once you’re used to wearing it, then you're all set.



The Jes Extender that goes with the noose-strap combo is very uncomfortable. But don’t let that discourage you from trying extenders. Check VacExtender Mod or the VLC tugger (if you're uncircumcised like me) as they go along with extenders. I have these two so I’m experienced in both.

Gains Happens with Girth


I stopped getting length gains due to how inconsistently I am with using the Jes Extender. But my wife says I got a thicker penis now. I currently have a 5.75-inch erect girth, and I was about to hit 6 inches in a few weeks if I continued using the extender.

Wear it regularly


With extenders, where most men fail is in the commitment part. Hey, it’s not their fault though, as not everyone has the time to use them until they reached their goal. I wore mine to work, church, concerts, even on dates. I can’t think of any place I went to that I don’t have my extender with me.

Not a scam


After 6 months, I gained one inch in erect length and one inch in erect girth. I used to be 6”x5”, now I am 7”x6”. I previously do jelqing and pumps, and never have I gained these much increase. I guess extenders are not a gimmick after all.

Aiming more for erect gains


I have not checked any erect gains, but my flaccid penis is now 5 inches as opposed to just 4.5 inches when I started four months ago. But I’m more about getting erect gains. I will try the 1500 grams and see if that would help.

Good for my curved penis


During the first six months, I wore the Jes Extender for 6 to 7 days per week, 8 to 12 hours per day. I always have it whenever possible. After six months, I reduced the frequency to just 5 days per week. Nowadays, I use less frequently. I had a slightly curved penis, and the extender does make it straight.

Progress is slow


I personally have a Jes Extender, and I’m quite satisfied with it. If you are thinking of buying one, be patient as the progress is gradual. Good luck.


  1. “Australian Medical Products & Services AMPS Pty Ltd – Penile Traction Splint.” Therapeutic Goods Administration, Department of Health, Australian Government, 30 Apr. 2012.[]
  2. “Import Alert 89-08.”, U.S. Food and Drug Administration (FDA), 26 Aug. 2019.[]
  3. Nowroozi, Mohammad Reza, et al. “Applying Extender Devices in Patients with Penile Dysmorphophobia: Assessment of Tolerability, Efficacy, and Impact on Erectile Function.” The Journal of Sexual Medicine, vol. 12, no. 5, May 2015, pp. 1242–47. PubMed, doi:10.1111/jsm.12870.[]
  4. Siana, J. E., et al. “Comparison of Self Reported and Observed Length, Width, and Colour of Scar Tissue.” Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery, vol. 26, no. 2, 1992, pp. 229–31.[]
  5. Oderda, Marco, and Paolo Gontero. “Non-Invasive Methods of Penile Lengthening: Fact or Fiction?” BJU International, vol. 107, no. 8, Apr. 2011, pp. 1278–82. PubMed, doi:10.1111/j.1464-410X.2010.09647.x.[]
  6. Hurn, Wendy. “Andrology.” North Bristol NHS Trust, NHS, 14 Oct. 2013.[]
  7. Rhoden, E. L., et al. “Prevalence of Peyronie’s Disease in Men over 50-y-Old from Southern Brazil.” International Journal of Impotence Research, vol. 13, no. 5, Oct. 2001, pp. 291–93.[]