Quick answer
39Thirty caps use stretch fabric with a single size range (usually S/M or L/XL), while 59Fifty caps are fitted and require exact head measurement. For most people, 39Thirty offers easier fit; 59Fifty gives a more tailored look.
Why sizing differs between 39Thirty and 59Fifty
The 39Thirty is a stretch-fit cap made with polyester or spandex blend, so it flexes to accommodate a range of head sizes. That means you choose between two size ranges (S/M or L/XL) rather than a specific number. The 59Fifty is a structured fitted cap with no stretch—it comes in precise sizes (like 7 1/8 or 7 3/8) and requires accurate head measurement.
If you're between sizes or prefer a snug but forgiving feel, 39Thirty is more forgiving. If you want a classic, clean look without any excess fabric, 59Fifty is the traditional choice.
Common sizing mistakes to avoid
One common mistake is assuming a 39Thirty S/M will fit the same as a 59Fifty size 7. They are not equivalent. Always measure your head circumference in inches or centimeters, then compare to the brand's size chart. Another pitfall is ignoring the stretch limit—39Thirty caps can feel tight if your head is at the upper end of the range, so if you're borderline, go up to L/XL.
Also, note that 59Fifty caps are often pre-shrunk but can still shrink slightly with washing. For 39Thirty, avoid high heat drying to preserve the stretch fibers.
How to find your Flex Fit cap size
- Measure your head circumference: Use a flexible tape measure around your head just above your ears and across your forehead where the cap will sit. Record the measurement in inches or centimeters. Common mistake: measuring too loosely or too high on the head. Keep the tape snug but not tight.
- Compare to the size chart: For 39Thirty caps, if your head measures 21 1/8"–22 7/8" (53.5–58 cm), choose S/M. For 23"–24 3/8" (58.5–62 cm), choose L/XL. For 59Fifty caps, use a fitted size chart (e.g., 7 = 22", 7 1/8 = 22 3/8", 7 1/4 = 22 3/4"). Checkpoint: If you're between sizes on a 39Thirty, go up to L/XL. For 59Fifty, try both adjacent sizes if possible.
- Try the cap on and adjust: Put the cap on and check for pressure points or gaps. A 39Thirty should feel snug but not leave red marks. A 59Fifty should sit level on your head without tilting or sliding. Common mistake: ignoring tightness in the front or back. If the cap leaves deep indentations, it's too small.
Product facts
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Somerset Patriots 2026 39Thirty Stars and Stripes Flex Fit Cap: This cap is a 39Thirty style with a stretch flex fit. You only need to choose between S/M or L/XL—no exact head measurement required, making it a quick grab-and-go option.
Somerset Patriots 2026 39Thirty Stars and Stripes Flex Fit Cap
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Somerset Patriots New Era 39Thirty Poly Stretch Flex Fit Co-Branded Cap: This New Era 39Thirty Poly Stretch Flex Fit cap uses a stretch fabric for all-day comfort. The co-branded design adds team pride, and the stretch fit accommodates a range of head sizes without needing a precise measurement.
Somerset Patriots New Era 39Thirty Poly Stretch Flex Fit Co-Branded Cap
