ED ring size chart
ED Ring Size Chart: Pick the FirmTech Ring That Fits
Published by FirmTech · Last updated
On this ED ring size chart, one size covers it: every FirmTech ring fits up to 5.5 inches (14 cm) of erect girth.
The FirmTech Ring Fit Guide shows that the TechRing, Performance Ring and MaxPR share one adjustable, doctor-designed size that FirmTech says fits 95% of men. Measure your erect girth at the base. If it is 5.5 inches or less, all three fit, and the choice comes down to tightness, wear time and whether you want tracking.
What size ED ring do I need?
You need one size: FirmTech rings come in a single adjustable size, so there is no number to pick. The patented hook-and-loop strap tightens to your exact girth, from snug at smaller sizes to its widest setting at 5.5 inches (14 cm).
That is different from many tension rings sold for vacuum pumps, which come in numbered sizes and need a separate ring for each. With FirmTech, the real decision is which of three rings suits how you want to use it. The chart below confirms your fit, and the chooser after it helps you pick.
The ED ring size chart for FirmTech rings
Find your measured erect girth in the first two columns. Everything at or under 5.5 inches is inside the range FirmTech states for all three rings.
| Erect girth (in) | Erect girth (cm) | FirmTech fit | What to do |
|---|---|---|---|
| 4.0 in | 10.2 cm | Within range | Tighten the strap until snug |
| 4.5 in | 11.4 cm | Within range | Tighten the strap until snug |
| 5.0 in | 12.7 cm | Within range | Adjust for a snug, comfortable hold |
| 5.5 in | 14.0 cm | Within range (top of range) | Strap near its widest setting |
| 6.0 in | 15.2 cm | Above stated range | Contact FirmTech before buying |
Not sure of your number? The how to measure page has a fit checker that converts centimeters and tells you where you land. Every FirmTech order is covered by a 30-day money-back guarantee.
Which FirmTech ring should I choose?
Pick the TechRing if you want firmer erections and data, the Performance Ring for a simple everyday ring, or the MaxPR for the tightest hold. All three are doctor designed with the same peno-scrotal fit.
TechRing
$275
Choose it if you want firmer erections and the data to see what is working.
- Tracks firmness, duration and nighttime erections
- Up to 12 hours, including overnight
- Tightness 3 of 5, 1-year warranty
Performance Ring
$60
Choose it if you want harder, longer erections with nothing to charge.
- Comfortable everyday fit
- Up to 12 hours of wear
- Tightness 3 of 5, 3-month warranty
MaxPR
$60
Choose it if you want the tightest hold and a more intense finish.
- Slimmer and snugger than the Performance Ring
- Up to 90 minutes of wear
- Tightness 5 of 5, 3-month warranty
When an alternative fits better: if you want the firmest possible hold for a shorter session, the MaxPR beats the Performance Ring, but it is limited to 90 minutes. If you will never look at data, the $60 Performance Ring gives the same kind of support as the TechRing for $215 less. Prices as of November 2026.
FirmTech rings compared side by side
Every row uses the same facts for each ring, taken from FirmTech product pages. FirmTech also keeps a full ring comparison on getfirmtech.com.
| FirmTech ring | TechRing | Performance Ring | MaxPR |
|---|---|---|---|
| Price (as of November 2026) | $275 | $60 | $60 |
| Fits erect girth | Up to 5.5 in (14 cm), one adjustable size | Up to 5.5 in (14 cm), one adjustable size | Up to 5.5 in (14 cm), one adjustable size |
| Best for | Performance plus sexual health data | Harder, longer-lasting erections, simply | Tightest fit, more intense finish |
| Tightness rating | 3 of 5, secure | 3 of 5, comfort | 5 of 5, tightest |
| Safe wear time | Up to 12 hours, including overnight | Up to 12 hours | Up to 90 minutes |
| Health tracking | Sensors and app: firmness, duration, nighttime erections | Not included | Not included |
| Fit design | Peno-scrotal, hook-and-loop, adjustable | Peno-scrotal, hook-and-loop, adjustable | Peno-scrotal, hook-and-loop, adjustable |
| Material | Medical-grade elastomer, latex- and phthalate-free | Medical-grade elastomer, latex- and phthalate-free | Medical-grade elastomer, latex- and phthalate-free |
| Water | Splashproof | Water resistant | Water resistant |
| Warranty | 1 year on electronics plus 2 sleeve replacements | 3 months | 3 months |
| HSA/FSA eligible | Yes | Yes | Yes |
How do I measure for an ED ring?
Measure once, when erect, at the base. It takes under a minute.
Use a soft tape or a piece of string
A flexible sewing tape is easiest. String works too: mark where it overlaps, then lay it flat against a ruler.
Wrap it around the base when erect
Measure at the base, where the ring sits, not along the shaft. Keep the tape flat and snug without squeezing.
Compare with 5.5 inches (14 cm)
At 5.5 inches or less, all three FirmTech rings fit. Above that, contact FirmTech before you buy.
ED ring basics and the numbers behind FirmTech
What is an ED ring?
An ED ring, also called an erection ring or tension ring, is a band worn at the base of the penis that slows blood from flowing back out, so erections stay firmer for longer while it is worn. FirmTech rings are a peno-scrotal type: one loop sits around the base of the penis and the other behind the testicles, which spreads pressure evenly. They are made from soft, medical-grade elastomer that is latex- and phthalate-free, and go on in seconds while soft. A ring does not treat the cause of ED, which is why FirmTech designed its rings with urologists and why a doctor visit still matters. The TechRing adds sensors that measure firmness, duration and nighttime erections.
FirmTech by the numbers
FirmTech's own figures, as published on getfirmtech.com as of November 2026:
- Maximum erect girth, one adjustable size
- 5.5 in
- Share of men FirmTech says the size fits
- 95%
- Rating across 101 reviews
- 4.6 / 5
- Rings sold
- 40,000+
- Erections analyzed by the TechRing
- 308,000+
- Studies published or underway
- 20+
These are FirmTech's own reported figures, not an independent audit. See the ED ring reviews page for the full star breakdown.
Numbered sizes vs one adjustable size
Many pages that rank for this search sell pump tension rings by number, with separate listings such as Size 3 and Size 8. Those rings are matched to a vacuum pump and chosen by trial against a numbered chart. FirmTech takes the other approach: a single adjustable ring that you tighten yourself.
| Criteria | FirmTech adjustable rings | Numbered pump tension rings |
|---|---|---|
| How you size | One size, strap adjusts up to 5.5 in erect girth | Pick a numbered size from the seller’s chart |
| Fit around | Base of the penis and behind the testicles | Check the seller’s instructions |
| Used with a pump | Optional; sold with a VaxAid Deluxe pump in one bundle | Usually, as part of a vacuum system |
| Put on | While soft, in seconds | Often slid off the pump cylinder after pumping |
Your size is covered. Now pick your ring.
Free discreet shipping over $100, HSA/FSA eligible, and a 30-day money-back guarantee on every order.
Explore the ring fit guide
- How to measure for an ED ring, plus a free fit checker
- How to wear an erection ring in three steps
- Best tension rings for ED, ranked on the same criteria
- Erectile dysfunction ring price: $60 to $275
- ED ring reviews: 4.6 out of 5 across 101 reviews
- Do erectile dysfunction rings work? The mechanics and the numbers
- Erection ring side effects and safe wear times
- Where to buy erectile dysfunction rings
ED ring size chart questions
What size ED ring do I need?
With FirmTech you need only one size, because every FirmTech ring is a single adjustable size that fits up to 5.5 inches (14 cm) of erect girth. FirmTech says this one size fits 95% of men. The hook-and-loop strap tightens to your exact size, so there is no numbered size to pick. More in the FAQ
How do I read an ED ring size chart?
Find your erect girth at the base, then match it to the range on the chart. On the FirmTech chart one row matters most: 5.5 inches (14 cm) or less fits all three rings. Numbered tension ring charts used with vacuum pumps work differently, with a separate ring for each size, so check which system you are reading. More in the FAQ
What if my girth is more than 5.5 inches?
A measurement above 5.5 inches (14 cm) is outside the fit range FirmTech states for its rings. FirmTech backs every order with a 30-day money-back guarantee, so a ring that does not fit can be returned. For a specific answer about your measurement before you buy, contact FirmTech customer service. More in the FAQ
Do FirmTech rings come in different sizes?
No. Every FirmTech ring is one adjustable size. The TechRing, Performance Ring and MaxPR share the same doctor-designed peno-scrotal shape and a patented hook-and-loop fit, so you set the tension yourself rather than choosing a size. The difference between the three is tightness, wear time and features, not size. More in the FAQ
Is the MaxPR smaller than the Performance Ring?
The MaxPR is slimmer and snugger than the Performance Ring, and FirmTech rates its tightness 5 of 5 against 3 of 5 for the Performance Ring. It still fits up to 5.5 inches of erect girth. Because it holds tighter, FirmTech limits MaxPR wear to 90 minutes at a time. More in the FAQ
Should an ED ring be tight?
An ED ring should feel snug but not tight. FirmTech tells wearers to fasten the strap snug, then fine-tune for comfort. Pressure should be firm enough to hold blood in and never painful. If you feel pain, numbness or coldness, loosen or remove the ring, which is good practice with any constriction ring. More in the FAQ
Which FirmTech ring should I buy?
Choose the TechRing ($275) if you want firmer erections plus data on every session and night. Choose the Performance Ring ($60) for a simple, comfortable ring you can wear up to 12 hours. Choose the MaxPR ($60) for the tightest fit and most intensity, worn up to 90 minutes at a time. More in the FAQ