Find your correct cylinder size.
One measurement, about two minutes. You will need a strip of paper, a pen, and a ruler.
Go to the size calculatorCylinder diameter determines both comfort and performance.
A cylinder that is too wide cannot maintain consistent vacuum, which reduces effectiveness and extends session time. A cylinder that is too narrow restricts expansion and causes contact with the cylinder wall, which is uncomfortable and counterproductive.
The correct diameter seals securely at the base and allows full expansion. This page identifies that diameter for you.
One measurement is required: girth, the circumference at the thickest point of the shaft.
What you need: a strip of paper or a soft measuring tape, a pen, and a ruler.
Method A: Measuring erect
Use this method if you can achieve an erection, full or partial. It produces the most accurate result.
- Wrap the paper strip around the thickest point of the shaft. It should rest against the skin without compressing it.
- Mark the point where the paper overlaps.
- Lay the paper flat against a ruler and read the distance from the end to your mark.
- Record the number, in inches or centimeters.
Method B: Measuring flaccid
Use this method if an erection is not currently achievable. This is common, whatever the reason, and it produces a reliable result when the calculator's flaccid setting is selected.
- Measure at normal room temperature. Avoid measuring directly after bathing, swimming, or exercise.
- Wrap the paper strip around the thickest point of the shaft. Rest it against the skin without compressing.
- Mark the overlap, lay the paper flat against a ruler, and read the number.
- Record the number and select "Measured flaccid" in the calculator. It applies a standard expansion allowance to estimate your size under vacuum.
Enter your measurement below. The calculator converts it to a recommended cylinder diameter from our catalog.
Select flaccid if you used Method B. The expansion allowance is applied automatically.
Every available diameter, with the girth range each one serves.
| Diameter | In cm | Girth range served | Lengths |
|---|
Begin with the size the calculator recommends. The correct fit seals snugly at the base without pinching. If the recommended size does not feel right after several sessions, the adjacent size is the appropriate next step.
Yes. Use Method B: measure flaccid at room temperature and select "Measured flaccid" in the calculator. The expansion allowance is applied automatically. Many of our customers size themselves this way.
No. Diameter controls the seal and your comfort, and it is the measurement that requires precision. Length only needs to provide adequate room. The 9 inch accommodates most men; the 12 inch is available where additional space is needed or preferred.
No. Girth varies considerably between men, and the catalog range reflects that. If you doubt the reading, measure once more with the paper resting against the skin without compressing, and record the larger of the two readings.
It can. Measurements may change with consistent device use, and post-surgical recovery can also affect them. If your cylinder begins to feel tight at the base, or the shaft contacts the cylinder wall, remeasure and size accordingly.
Yes. Measure the inside of the cylinder opening at its widest point with a ruler. If your current cylinder is within one size of the calculator's recommendation, your measurement is consistent.
Still not certain?
Sizing is the most common question our support team handles. Send your measurement and we will confirm your size personally, typically within one business day.
Contact support