ED ring size chart
FirmTech rings come in one adjustable size that fits 95% of men, up to 5.5 inches (14 cm) of erect girth, so most men do not need to choose a size.
Published by FirmTechLast updated November 2026
You do not need to pick a size with FirmTech. The TechRing, Performance Ring and MaxPR share one adjustable size that fits up to 5.5 inches (14 cm) of erect girth, which FirmTech says covers 95% of men. A hook-and-loop strap sets the tension to your exact size.
| Erect girth at the base | TechRing, Performance Ring, MaxPR | Notes |
|---|---|---|
| 5.5 in (14 cm) or less | Fits | The adjustable strap sets the tension to your size. Covers 95% of men, per FirmTech. |
| Over 5.5 in (14 cm) | Not designed to fit | Contact FirmTech before buying. |
FirmTech rings use a peno-scrotal design, so fit depends on two loops, not one. The first sits under the testicles and the second around the base of the penis. The strap should feel snug and secure, never painful. The Performance Ring and TechRing are rated 3 of 5 for tightness, and the MaxPR, a slimmer and snugger version, is rated 5 of 5. If the Performance Ring feels loose even at its tightest setting, the MaxPR is the step up. If anything feels painful or numb, loosen it or take it off. Every ring is covered by a 30-day money-back guarantee if it simply does not fit.
FirmTech rings are not designed for erect girth over 5.5 inches (14 cm), so ask FirmTech before you order. You can reach the team through the FirmTech contact page. For a side-by-side of every ring, see the ED ring reviews comparison.
More answers on reviews, price, fit and safety in the full ED ring FAQ.
With FirmTech you do not need to pick a size. One size fits 95% of men, up to 5.5 inches (14 cm) of erect girth, and the hook-and-loop strap adjusts to your exact size. All three FirmTech rings share that fit range.
See this answer in the FAQ: What size ED ring do I need?When erect, wrap a soft tape measure or a piece of string around the base of the penis. If it measures 5.5 inches (14 cm) or less, a FirmTech ring fits. If you used string, mark it and lay it against a ruler.
See this answer in the FAQ: How do I measure for an ED ring?FirmTech offers a 30-day money-back guarantee, so a ring that does not fit can be returned. Start a return online through the returns portal linked from FirmTech’s contact page, or email customer service with your order number.
See this answer in the FAQ: What if my ED ring does not fit?The MaxPR is the tightest, rated 5 of 5 for tightness on FirmTech’s product page. It is slimmer and snugger than the Performance Ring, which is rated 3 of 5. Because of the extra pressure, the MaxPR is worn for up to 90 minutes rather than 12 hours.
See this answer in the FAQ: Which FirmTech ring is the tightest?A peno-scrotal ring loops around both the base of the penis and behind the testicles, instead of the shaft alone. FirmTech rings are designed with urologists to use this anatomical fit so pressure is spread evenly and blood is held where it is needed most.
See this answer in the FAQ: What does a peno-scrotal fit mean?FirmTech offers a 30-day money-back guarantee. If a ring does not meet your expectations for any reason, you can start a return online with your order number and email. Support replies to return and warranty emails within 1 to 2 business days.
See this answer in the FAQ: What is the FirmTech return policy?Compare the three FirmTech rings, or contact FirmTech with a fit question.
