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SizeGenetics Guarantee - A Bigger Penis Or Your Money Back

SizeGenetics™ removes all the risk from buying a penis enlargement device. The method behind our devices has been clinically tested and proven to work, so you can purchase with full confidence that SizeGenetics™ will extend your penis safely and effectively. Read more about our method here

Our money back guarantee promises that your SizeGenetics™ will work for you or we’ll refund you your full purchase price.

You’ve got nothing to lose, and everything to gain!


Your safety

Our penis extenders have been clinically tested and have been certified as a medical type one device. Use SizeGenetics™ as instructed and you should never experience an injury.

High quality

Don’t settle for a cheaper, inferior device that can at best, break during use and cost you a small fortune in spare parts, or at worst, seriously injure your penis. SizeGenetics™ is manufactured to the highest standards using the finest quality materials, and every single device must pass our strict quality testing before it is allowed to be sold.

Penis Extension

We firmly believe that SizeGenetics™ is the most effective penis extender device available on the market. We are backed by clinical testing, doctor endorsements, years of research and real user testimonials, proving that it can work for everyone, including you!
You’ll find our money back guarantee really simple, because we believe 100% that SizeGenetics™ will work for you.


Simply use your SizeGenetics™ device for 120 consecutive days (4 months). In the highly unlikely event that you don’t see any increase in the size of your penis (or improvement in the curvature of your penis if using the device to treat peyronie’s/bent penis syndrome), get in touch with us within 6 months of receiving your device to request your refund.

Why do you need to use your device for 4 months?

While many of our customers begin to see gains within the very first few weeks, the speed of results varies from person to person. By using the SizeGenetics™ device daily for 4 months, you’ll be allowing sufficient time for the device to work for you.

To qualify for a refund, we will need to see the following documentation as evidence that you have used your SizeGenetics™ device in accordance with the instructions:

A before photograph and an after photograph of your penis next to a measuring device such as a tape measure or ruler (you must be wearing your SizeGenetics™ device in each photo, and the average traction of the device must be visible).

A diary/log detailing the days and the number of hours you have used your SizeGenetics™ device throughout the four months, including the amount of traction used each time. To qualify for a refund you must have used the device for at least 5 hours daily, at a minimum of 1200g traction, for at least 4 months.

We have made a tool called My Diary to help you keep track of your training – Create and follow your results already today – Click here

To request your refund, simply email your request along with the above supporting documents to support@sizegenetics.com.

Please note: Every SizeGenetics™ device is disinfected and delivered to you in a sealed plastic bag. Once this bag is opened, your device cannot be returned or refunded unless you are requesting a refund under our money back guarantee terms above.

Choosing SizeGenetics™ is risk free – we guarantee you will extend your penis length (quickly and safely) or we’ll give you your money back!

SizeGenetics™ Doctor's Endorsements


Dr. Jorn Siana
Specialist in General and Plastic Surgery.
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Doctor Finn Knudsen

Dr. Finn Knudsen 
Specialist in Plastic Surgery.
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