A snap brim is one of the defining features of a man's hat and most commonly found on fedoras. The shape, size and flexibility of a brim can vary from style to style. While this type of brim is found most often in men's hats, some women's hats also have this feature. There is also an Australian-based brand called Snap Brim.

Simply defined by Dictionary.com, a snap brim is one that can be turned up or down on a hat. These are often called snap-brim hats. Fedoras are a common type of snap-brim hat that usually style the brim up in back and down in front. The size of the snap brim varies depending on the hat's style, but larger widths provide greater protection from the sun.

Patented in 2005, the Snap Brim is an accessory that attaches to hardhats to provide additional protection from the elements. The Australian-based company Snap Brim markets the product to construction, power utility and mining companies as a simple solution to protecting employees from too much sun exposure. Snap Brims are made of a durable material and fit around the outside of a hardhat, providing shade to the face and neck.

Fedoras are not the only claim to fame for snap brims. Panama hats and top hats also commonly have snap brims. While the brims and hats are often made of felt, they can also be made out of other materials, including straw, cotton and suede. The surface can also be treated with a water resistant compound such as Teflon to make the brim more resistant to weather and staining. However, do not get the brim of any hat too wet; the hat will likely lose its shape.

Men with slender, top-heavy or long faces should opt for a medium-width brim of about two inches, as should those with a prominent jaw. If you have a square or pear-shaped face, you will likely look best in a hat with a wide snap brim, which is about three inches. A wider brim that is fully snapped down can also take emphasis off of large ears.