Frundies 101 - An Introduction to Men's Underwear Styles

Some of the most common questions we receive from customers here are Frundies relate to the differences between the many types of underwear styles we offer for guys. As we offer 100s of styles from manufacturers all over the world, we've done our best to categorize them to help you find the styles you're looking for. Here's a quick run down on the differences between our classifications:


Men's Underwear & Swimwear Styles:

mens brief underwear


Arguably the style that started the men's underwear revolution, men's briefs we're introduced in the 1930s. They are designed to offer the support of a jockstrap with the benefit of added comfort and style. They are made from a tight fitting material and have a high leg opening. The fabric of the briefs covers the full rear seat area.  Briefs can come with or without a front fly opening. Originally available in only white, briegs were dubbed "tighty-whities" and were the standard in men's underwear up until the 1970s.

Bikini Brief

 A spin off the the men's brief inspired by the success of women's bikini swimwear, bikini briefs high a higher leg opening than briefs with the front and rear fabric panels often only being connected by the waistband itself. Bikini briefs came into fashion in the 1970s. Most bikini briefs do not include a front fly.

Boxer Shorts

Boxers, or boxer shorts, derive their name from their original intended use a shorts used by boxers during the early half of the 20th century. Boxers tend to be a loose fitting garment with longer leg openings than briefs. Most boxers include a functional or faux front fly.
Mens Boxer Brief Underwear

Boxer Brief

A hybrid of the brief and the boxer short, boxer briefs came into fashion during the 1980s. They offer the support of a brief with the more modest leg coverage of the boxer short. Like briefs, they are available with or without a functional fly.


The origination of the g-string is believed to have dated back to the loincloths of early man. A front panel covering the genitals was made of woven vegetation or leather and fastened around the waist and groin area via a string consisting of twine, leather, or other available cordage. G-strings consist of a fabric panel in the front only and fastened by rope, lace, or elastic material unlike thongs which typically feature a small amount of fabric in the seat area. G-strings typically do not include a front fly.


The modern jockstrap was believed to have originated during the late 19th century as a means of support for the genitals for men riding horseback and bicycles. It as worn under the loose fitting undergarments of the time. The jockstrap ,or jock, consists of the front fabric panel, waistband, and two elastic straps which are worn around the legs. There is no fabric in the rear seat area. Jockstraps continue to see use in a variety of athletics with the wide waistband and leg elastic providing support to the genitals. For sports many jockstraps include a pocket for wearing a protective cup. Today jocks are worn as much for fashion as function and are available in a variety of styles and fabrics.
mens thong underwear


Not to be confused with the g-string, the thong consists of a front fabric panel with high leg openings and a rear fabric panel with minimal fabric coverage. The two panels are connected on the sides by fabric and a waistband. Thong underwear is often called a "t-back" or "whale tail" due to its similar appearance to a whale's flukes.
Mens Trunks Underwear


A further variation of the brief and boxer brief, men's trunks feature a shorter leg length than a traditional boxer short but longer than a brief. The leg openings of a pair of trunks are at or about the same length as the bottom of the front crotch panel.

Swim Brief

Similar in design to a men's brief, but without the front fly, the swim brief has long been used in competition swimming. The high leg openings offer freedom of movement when in the water white the fabrics tend to be synthetic to dry quickly and shed water. Most swim briefs include a drawstring to keep them secured and a front crotch panel for added modesty when wet.
Mens Swim Jammer

Swim Jammer

Just as the boxer brief is a more modest, longer leg version of the brief, the swim jammer is a longer leg version of the swim brief. While sometimes used for competitive swimming, the jammer tends to be used less in sports like water polo and diving where the additional fabric can restrict movement.
Mens Board Short

Board Shorts

Brought into fashion by the surf industry, board shorts are loose fitting swimwear with longer leg openings designed from synthetic fabric to dry quickly and stand up to abrasion from the board's surface and wax while not chaffing the wearer.  Board shorts are typically unlined and can be worn with nothing underneath or worn over a variety of underwear or swimwear styles.
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