Yupoong — Flexfit, YP Classics, and the Original Stretch-Fit Cap
Yupoong is a South Korean headwear company founded in Seoul in 1974, and it is the largest cap manufacturer in the world. The company began as a fabric exporter, moved into headwear production in 1977, and in 1994 invented the product that defined it: the original Flexfit cap, the first patented stretch-fit cap, which weaves polyurethane spandex through the crown and sweatband so the cap stretches to fit the head without a back closure. That invention created an entirely new category in headwear — the stretchable fitted cap — and Flexfit has been one of the most recognized names in the industry ever since. Today Yupoong holds the trademark rights to both the Flexfit and YP Classics brands, operates under a "zero defect" quality standard, and produces millions of caps annually for the global decorated-apparel and retail markets.
The thing to understand about Yupoong is the relationship between the names. Yupoong is the company. Flexfit is its patented stretch-fit brand. YP Classics is its adjustable cap line — snapbacks, truckers, dad caps, and beanies that fit one size with a back closure rather than stretching to fit. A buyer searching for a "Flexfit 6606" and a buyer searching for a "Yupoong 6606" are usually looking for the same cap, because the brands all trace back to one manufacturer. The distinction that matters at purchase is the fit system: Flexfit caps stretch and are sized (S/M, L/XL), while YP Classics caps are adjustable and one-size.
Flexfit — The Stretch-Fit Originals
The Flexfit line is built around the patented stretch-fit technology that started it all. These caps have no snapback, strap, or buckle — the spandex woven through the crown and sweatband lets the cap conform to the head for a fitted look with a comfortable, flexible hold. The line has expanded over three decades into several distinct technologies. The original Flexfit (the 6277 and related models) is the classic six-panel structured stretch cap that defined the category. Flexfit 210, launched in 2001, is a premium flat-bill fitted cap with a higher, more structured profile. Flexfit 110, launched in 2010, is a hybrid that combines Flexfit comfort with an adjustable snapback closure, giving the fitted look with one-size adjustability. Flexfit Delta, launched in 2015, is the most advanced — a seamless cap bonded without stitching, made from a stain-blocking, water-repellent material with a lightweight visor, for a clean, modern, premium finish.
YP Classics — Adjustable Snapbacks, Truckers, and Dad Caps
The YP Classics line covers the adjustable, one-size caps — the styles most associated with custom embroidery, screen printing, and retail brand programs. The 6606 Retro Trucker Cap is the flagship and the single most recognized blank cap in the decorated-headwear industry: a low-profile structured front with premium mesh back panels and a snapback closure, available in dozens of colors and the default choice for high-volume embroidery and heat-transfer work. The 6006 Classic Trucker is a five-panel flat-brim version with a seamless front panel that gives a larger print area. The 6245 Classic Dad Cap is the unstructured, low-profile, curved-brim style with a strapback closure. The line also includes flat-bill snapbacks (the 6089 and 5389), retro cotton-blend five-panel caps, and perforated and braided-rope variants. Rounding out YP Classics are the YP Beanies — hypoallergenic acrylic knit caps in cuffed and uncuffed styles.
Outdoor and Licensed Camo
Yupoong produces a substantial range of caps in licensed camouflage patterns, built on its Flexfit and YP Classics constructions. These include RealTree (the hunting-and-outdoor camo standard), MultiCam (the licensed military-developed pattern), Veil Camo, and Kryptek — each applied to fitted, mesh, and trucker cap bodies for the outdoor, hunting, fishing, and tactical markets. Yupoong also runs a sustainable line built from recycled materials for buyers prioritizing environmental sourcing.
Choosing a Yupoong Cap
The first decision is the fit system. A Flexfit cap (6277, 210, Delta) stretches to fit and is purchased by hat size (S/M, L/XL) — choose it for a clean, fitted look with no adjustable strap. A YP Classics cap or Flexfit 110 is one-size with an adjustable closure (snapback or strap) — choose it for adjustability and the classic snapback or trucker look. The second decision is the style: trucker caps (6606, 6006) have mesh back panels for ventilation and a casual, retro profile; structured fitted caps (6277, 210) have a fuller crown and a more polished look; dad caps (6245) are unstructured and low-profile; and Delta caps offer the most modern, seamless, premium finish. The 6606 Retro Trucker is the most universally popular and the safest starting point for most buyers, while the Delta line suits those wanting a more refined, technical cap.
Frequently Asked Questions
Are Yupoong and Flexfit the same thing?
Yupoong is the company; Flexfit is one of its brands. Yupoong, founded in South Korea in 1974, manufactures all Flexfit caps along with the YP Classics line and YP Beanies. So all Flexfit caps are made by Yupoong, but not all Yupoong caps are Flexfit — the YP Classics adjustable caps are also Yupoong products. When shoppers search "Flexfit 6606" or "Yupoong 6606," they are generally looking for the same cap.
What is the difference between a Flexfit cap and a YP Classics cap?
The fit system. Flexfit caps use patented stretch-fit technology — spandex woven through the crown and sweatband lets the cap stretch to fit the head, and they are sold in sizes (S/M, L/XL) with no back closure. YP Classics caps are one-size and adjustable, using a snapback, strapback, or buckle closure. Choose Flexfit for a fitted, no-strap look sized to your head; choose YP Classics for adjustable, one-size-fits-most caps in classic snapback, trucker, and dad-cap styles.
What is the Flexfit 110, and how is it different from the original Flexfit?
The Flexfit 110, launched in 2010, is a hybrid cap. It combines the comfort of Flexfit construction with an adjustable snapback closure, so it offers the fitted Flexfit feel in a one-size adjustable cap. The original Flexfit (such as the 6277) is a true stretch-fit cap with no closure, sized S/M or L/XL. The 110 is the choice for buyers who want Flexfit quality but prefer one-size adjustability over sized fitting.
How do you wash a Flexfit cap?
Yupoong recommends not machine-washing Flexfit caps, as it can damage the stretch-fit construction and the cap's structured shape. Instead, spot-clean with a damp cloth and mild detergent, and air-dry away from direct heat. Avoid submerging the cap or putting it through a washing machine or dryer, both of which can warp the crown and degrade the spandex in the sweatband.
What is the Flexfit Delta cap?
The Flexfit Delta, launched in 2015, is Yupoong's most advanced cap construction. It is bonded seamlessly without stitching, made from a stain-blocking and water-repellent material, and finished with a lightweight visor. The seamless construction gives a clean, modern surface ideal for both retail and decoration, and the stain-resistant, water-repellent fabric makes it more durable in wear than standard cotton caps. It is the premium, technical option in the Flexfit lineup.
Across the Flexfit, Flexfit 110, Flexfit 210, Flexfit Delta, and YP Classics lines, Yupoong covers nearly every cap style worth carrying — fitted stretch caps, adjustable snapbacks, mesh trucker caps, dad caps, knit beanies, and licensed camo patterns from RealTree, MultiCam, Veil, and Kryptek. Browse the full range in hats and beanies.
