Cock Rings for ED: Medical-Grade Constriction and Tension Rings Explained

Cock rings, also known as erection rings, ED rings, or tension bands, are among the simplest yet most effective devices for helping men achieve and maintain stronger erections. While often thought of as novelty items, medical-grade cock rings are precision-engineered therapeutic devices widely recommended by physicians as part of erectile dysfunction (ED) treatment. Millions of men across all ages experience ED due to factors such as aging, diabetes, cardiovascular disease, prostate surgery, or medication side effects. For many, oral medications or invasive procedures are not suitable options. In these cases, a safe, drug-free alternative like a medical constriction ring offers real benefits. By gently restricting blood flow at the base of the penis, these rings help maintain firmness for sexual activity, restore confidence, and improve intimacy. Unlike standard novelty cock rings, which vary widely in quality, medical-grade silicone ED rings and tension bands are carefully designed for comfort, safety, and consistent performance, making them an important part of modern ED therapy.

How Do Cock Rings for ED Work?

Medical cock rings are worn at the base of the penis after an erection has been achieved, often with the help of a vacuum erection device (VED). Once in place, the constriction ring slows the outflow of blood, helping maintain a firm erection long enough for intercourse. Unlike recreational rings, which may not be designed for safety or comfort, medical tension bands are precisely engineered in multiple sizes and tension levels to ensure proper fit, comfort, and reliable performance.

Some medical-grade rings include unique design features to improve comfort and function. For example, certain rings have top-side pressure bumps that strategically press against veins to better restrict blood flow, while a lower U-notch cradles the urethra to reduce pressure and allow ejaculation during use. These details make medical cock rings not only effective but also safe for long-term ED therapy when used correctly.

Because cock rings are frequently used in combination with VEDs, many men find it helpful to understand how these devices complement one another. If you’d like to explore this further, see our guide: What Is the Best Vacuum Device for Erectile Dysfunction? A Complete Guide to Medical-Grade Penis Pumps.

Medical-Grade Cock Rings vs. Standard Sex Rings

Medical-grade cock rings are specifically designed for erectile dysfunction therapy. They differ from standard sex rings in materials, sizing precision, and clinical design. Products from Timm Medical, Osbon, Encore, and Owen Mumford are widely recommended by urologists and men’s health specialists worldwide. Men who rely on these medical rings benefit from consistent results, safe use, and the reassurance that comes from using clinically developed devices.

Comparing Leading Brands of Medical Cock Rings

All medical-grade cock rings and tension bands sold at Medicinal Supplies are made from soft, durable silicone. This material provides the ideal balance of flexibility, comfort, and constriction strength while being safe for repeated use. What sets the brands apart is not the base material, but their sizing systems, tension levels, and unique design features. Below is a detailed overview of the most common options available.

Encore Silicone Penis Rings (Bands)

Encore silicone bands are among the most popular ED rings due to their consistent compression, wide sizing range, and ease of use. Offered in seven incremental sizes, they give men the ability to select a precise fit for optimal comfort and support. Known for their durability and affordability, Encore rings are a preferred choice not only for Encore vacuum erection devices but also for men using other systems who want a reliable, well-fitting ring.

• #3 – 1/2 in. (12.7 mm)
• #4 – 9/16 in. (14.22 mm)
• #5 – 5/8 in. (15.75 mm)
• #6 – 11/16 in. (17.27 mm)
• #7 – 3/4 in. (19.05 mm)
• #8 – 13/16 in. (20.57 mm)
• #9 – 7/8 in. (22.1 mm)

Owen Mumford Rapport Silicone Penis Rings (Bands)

Rapport bands by Owen Mumford provide the same level of precision sizing and reliability as Encore but are designed for Rapport VED systems. Available in seven sizes, they deliver smooth compression and a comfortable fit that many men find effective for long-term use. Though made for Rapport devices, they are often used successfully with other pumps, giving users flexibility without sacrificing performance.

• #3 – 1/2 in. (12.7 mm)
• #4 – 9/16 in. (14.22 mm)
• #5 – 5/8 in. (15.75 mm)
• #6 – 11/16 in. (17.27 mm)
• #7 – 3/4 in. (19.05 mm)
• #8 – 13/16 in. (20.57 mm)
• #9 – 7/8 in. (22.1 mm)

Pos-T-Vac Mach Penis Rings (Bands)

Pos-T-Vac Mach rings are built for men who want options in both size and constriction strength. Each of the four available sizes has a distinct tension level ranging from low to high, giving men the ability to fine-tune their experience. Their sturdy yet flexible silicone construction makes them a dependable choice for consistent performance during ED therapy.

• A141 – #5 Small, 0.25 in. (6.5 mm), high tension
• A148 – #6 Medium, 0.34 in. (8.6 mm), medium tension
• A143 – #7 Large, 0.43 in. (10.5 mm), standard tension
• A144 – #8 Extra Large, 0.55 in. (13.5 mm), low tension

Pos-T-Vac Ultimate Penis Rings (Bands)

Pos-T-Vac Ultimate rings are designed with a rounded, flexible profile that makes them one of the most user-friendly cock rings available. Made of soft medical-grade silicone, they can be reused 20–30 times and are safe for men with latex sensitivities. Available in five sizes, they allow users to choose a precise level of constriction, whether used on their own or in combination with a vacuum erection device.

• A121 – #X Extra Small, 0.31 in. (7.6 mm), high tension
• A122 – #1 Small, 0.35 in. (8.7 mm), high tension
• A123 – #2 Medium, 0.43 in. (11 mm), medium tension
• A124 – #3 Large, 0.55 in. (14 mm), low tension
• A125 – #4 Extra Large, 0.63 in. (16 mm), low tension

Osbon Constriction Penis Rings (Bands)

Osbon Constriction Bands are patented, medically engineered rings designed to balance comfort and effectiveness. They feature pressure bumps that restrict outflow to sustain erections while the lower U-notch cradles the urethra to allow ejaculation. This thoughtful design makes them a versatile solution for men seeking safety, performance, and comfort. They can be worn alone or combined with another ring to increase tension when needed.

• Size A – 0.875 in. (22 mm), standard tension
• Size B – 0.875 in. (22 mm), high tension
• Size C – 0.75 in. (19 mm), standard tension
• Size D – 0.75 in. (19 mm), high tension

Osbon Max Elasticity Penis Rings (Bands)

Osbon Max Elasticity Rings are designed for men who need a gentler level of constriction. Made of soft silicone, they feature pressure points for erection support along with a U-notch that relieves pressure on the urethra and allows ejaculation. This thoughtful, low-tension design makes them an excellent choice for men who find standard rings too tight but still want reliable erectile support.

• Medium – 0.75 in. (19 mm)
• Large – 0.875 in. (22 mm)

Osbon EZ Penis Rings with Body Shield

Osbon EZ Rings are known for their patented body shield that simplifies application and improves comfort. By creating a stronger seal while preventing scrotal tissue from being drawn into the cylinder, these rings make the transfer process faster and easier. Compatible with both Esteem and Classic VED systems, they provide dependable rigidity with reduced hassle, making them one of the most practical options available.

• #4 – 16 mm (0.625 in.)
• #5 – 17 mm (0.667 in.)
• #6 – 18 mm (0.708 in.)
• #7 – 19 mm (0.75 in.)

StayErec Elastic Penis Ring (Band)

StayErec Bands are made of soft, highly elastic silicone and designed as a one-size-fits-all option. They provide a natural feel while still delivering consistent constriction for ED support. Disposable after use, they are a convenient solution for men who prefer simplicity, hygiene, and ease of application over multiple ring sizes or reusable options.

• Universal one-size highly elastic band

Choosing the Right Cock Ring Size

Finding the correct size and tension is one of the most important steps in using a medical-grade cock ring safely and effectively. An ED ring that is too loose may fail to maintain rigidity, while a ring that is too tight can cause discomfort or restrict blood flow more than intended. The goal is to achieve a snug, supportive fit that maintains the erection comfortably for the duration of intercourse, typically no longer than 30 minutes at a time.

Most medical brands provide rings in graduated sizes ranging from 0.25 in. to 0.875 in. inner diameter. Men are often encouraged to try two or three different sizes to determine which provides the right balance of firmness and comfort. For example, Encore and Rapport offer fine size increments (#3 through #9), making it easier to fine-tune the fit. By contrast, Pos-T-Vac Ultimate rings are categorized more broadly (XS to XL) but include different tension strengths to adjust performance.

It is also important to consider the style of ring. Traditional silicone bands provide firm, consistent compression, while products such as the Osbon Max Elasticity bands use a softer silicone formulation for gentler constriction. The Osbon EZ Rings include an integrated body shield to improve comfort and placement, and StayErec bands provide a one-size elastic solution for men who prefer flexibility over precision sizing.

For first-time users, it may take some trial and error to find the perfect fit. Using water-soluble lubricant around the base of the penis and cylinder (if paired with a vacuum erection device) helps create a better seal and makes it easier to slide the ring on and off comfortably. Many men also benefit from having more than one size available, since factors such as medication, hydration, or time of day can slightly influence erection firmness. When in doubt, consulting with a urologist or healthcare professional can provide reassurance and help select the safest and most effective option.

ED Ring Size Chart

Selecting the correct size is one of the most important steps in using an ED penis ring safely and effectively. The chart below lists common medical-grade ED ring sizes across leading brands, with inner diameters shown in both inches and millimeters. Choosing the right fit helps ensure comfort, reliable performance, and optimal results.

Shop Medical Cock Rings at Medicinal Supplies

At Medicinal Supplies, we carry a full range of medical cock rings, ED tension bands, and silicone constriction rings from trusted brands such as Encore, Timm Medical, and Owen Mumford. Every item is authentic and shipped discreetly for your privacy. From versatile Encore silicone bands and patented Osbon EZ Rings to flexible StayErec options, our store makes it simple to find the right fit for your ED therapy. Use our ED Ring Size Chart to compare sizing across brands and select the solution that offers the comfort, support, and confidence you need.