Broadly, eyeglasses hinges come in three types: the flexible spring hinge, the standard or barrel hinge, and the hingeless design. Eyeglass hinges are not just a critical component of eyewear, they are the most important part of any pair of glasses. The hinges of eyeglasses allow the temples to fold, and they also affect the way your frames fit.

Whether you select sunglasses with conventional (standard) hinges, spring/flex hinges, or no hinges at all, over time, the twisting, stretching, bending, and everyday wear and tear on your glasses can cause the hinges to weaken and loosen. The frames you select will depend on your daily activities, style preferences, and budget. Specific designers and brands offer proprietary hinge technology for the active wearer, while others design glasses with standard hinges that are easy to repair. Consult this guide to learn more about the types of eyeglass hinges, and which is right for you.

Standard, Or Barrel Hinges

Standard hinges (also known as barrel hinges) are the most common type of eyeglass hinges. The barrel hinge design features a series of metal rings (barrels) that fit into each other like a zipper, with a small screw that slides inside to keep the barrels in place. Each barrel can be adjusted up or down with a tiny pair of pliers to provide a comfortable and secure fit. If you purchase a new pair of eyeglasses and they slide off the face or do not fit securely, a few barrels can be adjusted inside the hinge to provide a snug fit.

Standard hinges are easy to repair. With a simple eyeglass repair kit and a YouTube tutorial, just about anybody can repair their conventional eyeglasses hinges easily and affordably.

Standard hinges are durable. These hinges have been around almost as long as eyeglasses have been and they have a reputation for being easy to repair.

Standard hinges are more affordable. Thanks to the uncomplicated design and wide use of the barrel hinge, eyeglasses that feature them are often more affordable.

Adjustment may require a visit to the optician. If a pair of eyeglasses with standard hinges does not fit out of the box, your optician will have the proper tools and accessories to fit them correctly.

Glasses with standard hinges may fall off during running, jogging, and other rigorous activities. Temples attached with conventional hinges tend to be more rigid. If you lead an especially active lifestyle, this type of hinge is better suited to the office than to the gym.

Five-Barrel Vs. Seven-Barrel Hinges

Most standard eyeglass hinges are classified as three-, five-, or seven-barrel hinges. This refers to the number of interconnected barrels that comprise the hinge. For conventional hinges, five- and seven-barrel configurations are the most common. While seven-barrel hinges are sturdier, they’re also more difficult to adjust and repair. When choosing between five- and seven-barrel hinges, let your habits inform your decision. If you’re hard on your glasses, for example, five-barrel hinges may be a better option for you.

Spring/Flex Hinges

Known for its flexibility, the spring or flex eyeglass hinge offers the active wearer a snug fit that doesn’t pinch. Unlike standard or barrel hinges, spring/flex eyeglass hinges come with an attached spring that allows them to bend past ninety degrees. The spring itself takes the majority of the force when the glasses bend and twist, allowing this type of hinge to retain its initial balance and fit without the need for subsequent adjusting.

Spring hinges don’t require multiple adjustments. Spring hinges hold their initial balance, which is one of their most attractive attributes. While a pair of eyeglasses with a spring hinge may need a bit of adjusting when you first receive them, once they’ve been fitted to your face, they won’t need adjusting again.

Spring hinges are better suited to the active wearer. Since spring hinges allow the temples to hug the head for a secure fit, these glasses will stay in place during running, jumping, or jogging. This makes them a better choice for the active adult, and for children.

Spring hinges are complicated to repair. If your spring eyeglass hinges become damaged, you may need to visit your local optician to have them repaired. If you purchased glasses with proprietary hinge technology, returning them to the manufacturer is the best option.

Proprietary Technology in the Flexible Spring Hinge

A number of eyeglass manufacturers have developed proprietary technology for spring/flex hinges that bend in all directions to provide optimal durability and a more secure fit.

Hingeless Eyeglasses

One of the newest innovations in eyewear is a frames design without hinges, or ‘hingeless’ eyeglasses. Without the tiny, interworking parts of a hinge, this type of eyeglasses features curved temples sculpted to fit the shape of the wearer’s head. The frames are most commonly rimless and made in titanium or other sturdy but pliable material. This hinge ‘type,’ or lack of hinge, is perfect for the active wearer who participates in sports, labor-intensive work, or other rigorous activities.

Hingeless frames are tailored to you. Because hingeless frames feature flexible temples, your optician can bend and tailor them to provide a more secure or looser fit, depending on your preferences.

Frames without hinges are engineered for an active lifestyle. In a career or hobby where your glasses need to flex with your movements, hingeless frames are a perfect option. With their innovative, flexible temples, hingeless glasses are designed to grip the head and move with you.

A lack of hinges can result in a less precise fit on the nose. Hingeless glasses rely on their curved temples to hold the glasses to the head for a secure fit. Since there are no springs or barrels in hingeless frames, some wearers will experience the glasses moving around on the nose bridge. When purchasing hingeless glasses, make sure you measure carefully to achieve the correct temple length for a secure, comfortable fit.

Hingeless glasses can be difficult to repair. If a conventional hinge breaks, in many cases, you can purchase an eyeglasses repair kit and repair the broken hinge yourself. This is not the case for hingeless glasses. Due to their proprietary, highly innovative designs, hingeless glasses must be returned to the manufacturer for repair in most cases.