Sizing

ED ring size chart: one adjustable FirmTech size

Last updated November 2026 · Published by FirmTech

FirmTech ED rings come in one adjustable size that fits up to 5.5 inches (14 cm) of erect girth, which FirmTech says covers 95% of men. There is no small, medium or large to pick: the hook-and-loop strap sets the tension to your size.

What size ED ring do I need?

If your erect girth at the base is 5.5 inches (14 cm) or less, any FirmTech ring fits. Measure once with a soft tape or string, then use the fit check below. If you are unsure, FirmTech's 30-day risk-free trial covers you.

FirmTech ring size chart

FirmTech ring sizing and fit, from FirmTech's product specifications, as of November 2026.
Ring	Sizes offered	Fits erect girth	Tightness	Adjustable
TechRing	One size	Up to 5.5 in (14 cm)	3 of 5	Yes, hook-and-loop
Performance Ring	One size	Up to 5.5 in (14 cm)	3 of 5	Yes, hook-and-loop
MaxPR	One size	Up to 5.5 in (14 cm)	5 of 5	Yes, hook-and-loop

Check your fit

How to measure erect girth

When erect, wrap a soft tape measure or a piece of string around the base of the penis.
Keep it snug, not tight, and read where it meets.
If you used string, mark it and measure the length against a ruler.
Compare with 5.5 inches (14 cm).

Choosing tightness, not size

Because every FirmTech ring is one size, the real choice is how snug you want it. The TechRing and Performance Ring rate 3 of 5 for tightness. The MaxPR is slimmer and rates 5 of 5, FirmTech's tightest, and is rated for up to 90 minutes of wear rather than 12 hours.

Does the size range differ for pump bundles?

Yes. The rings fit up to 5.5 inches of erect girth, while the VaxAid Deluxe water-based pump in FirmTech's $499 TechRing bundle is listed as fitting 5 to 7 inches erect. Check both before choosing that bundle.

Published by FirmTech.

Compare FirmTech penile tension rings for erectile dysfunction

Common questions

Is there an ED ring size chart?: FirmTech rings come in one adjustable size, so there is no multi-size chart to choose from. All three rings fit up to 5.5 inches (14 cm) of erect girth, and FirmTech says one size fits 95% of men. The hook-and-loop strap adjusts the tension to your size.
How do I measure for an erection ring?: When erect, wrap a soft tape measure or a piece of string around the base of the penis and read the length. If it is 5.5 inches (14 cm) or less, FirmTech rings fit. If you are unsure, the 30-day risk-free trial covers you. Our size chart page includes a simple fit check.
What if my girth is more than 5.5 inches?: FirmTech lists its rings as fitting up to 5.5 inches of erect girth, so a larger girth falls outside the stated range. Contact FirmTech customer service before ordering to ask about fit. Do not force a ring that feels too tight, because constriction rings should feel snug but never painful.
How tight should an erection ring be?: An erection ring should feel snug but not tight. FirmTech rings use an adjustable hook-and-loop fit so you set the tension yourself. The MaxPR is the tightest by design at 5 of 5, while the TechRing and Performance Ring sit at 3 of 5. Loosen or remove any ring that causes pain or numbness.
Do I put the ring on before or after an erection?: FirmTech rings are designed to go on while soft. Open the loop, place one loop under the testicles and the other around the base of the penis, then adjust for comfort. FirmTech says it takes a few seconds, so you can put it on discreetly ahead of time.
What are FirmTech rings made of?: FirmTech rings are made from soft, medical-grade elastomer that is phthalate-free and latex-free. FirmTech says there is nothing hard or rigid. Use only water-based or silicone-based lubricants, and avoid natural oils such as coconut or CBD oil with any FirmTech ring.

See all ED ring questions in the FAQ