TWF Headwear Size Guide

This size guide covers TWF Headwear, available in five sizes from XSM through to XLG. Sizing is based on head circumference, measured approximately 1 inch (25mm) above the ear. Both cm and inches are provided. TWF use abbreviated size codes (XSM, SML, MED, LGE, XLG) — use these codes when ordering.

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Body Measurement Point
TWF headwear measurement guide showing head circumference measured 1 inch above the ear
How to Measure

Use a soft tape measure and take the measurement directly against the skin.

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    Head Circumference Wrap a soft tape measure around your head approximately 1 inch (25mm) above the ear — this is the point where the headwear will sit. Keep the tape level and snug all the way around. Match your measurement to the size table below.

The measurement gives an estimated best fit. If between sizes, size up for a more comfortable fit or size down for a snugger feel.

Sizing Table — TWF Headwear
TWF Size Code Head Circumference (cm)
XSM 50.5–53 cm
SML 53–55.5 cm
MED 55.5–58 cm
LGE 58–60.5 cm
XLG 60.5–63 cm

Measure approximately 1 inch (25mm) above the ear. TWF use abbreviated size codes — use these when ordering. If between sizes, size up for comfort.

Fit Notes — TWF Headwear
  • Size based on head circumference measured approximately 1 inch (25mm) above the ear, where the headwear will sit.
  • TWF use their own abbreviated size codes (XSM, SML, MED, LGE, XLG) rather than standard S/M/L labels — use the code column when ordering.
  • The measurement gives an estimated best fit. If between sizes, size up for a more comfortable, relaxed fit or size down for a snugger, more secure feel.
  • The headwear should sit flat and evenly around the head without gaps or excessive bunching. If it feels tight across the forehead after a short time, try the next size up.
  • Unsure? Contact our team or call +44 1827 330600.
Frequently Asked Questions — TWF Headwear

Measure around your head approximately 1 inch (25mm) above the ear using a soft tape measure. Match your measurement in cm or inches to the size table above and note the corresponding TWF size code. Use that code when placing your order.

TWF use abbreviated size codes rather than standard S/M/L labels. XSM is the smallest size (50.5–53 cm / 20–21"), SML covers 53–55.5 cm, MED covers 55.5–58 cm, LGE covers 58–60.5 cm, and XLG is the largest (60.5–63 cm / 24–25").

Measuring 1 inch (25mm) above the ear gives the circumference at the point where the headwear will actually sit on the head. Measuring at a different height — such as across the forehead or lower on the skull — can give a different circumference and result in an inaccurate size selection.

Size up for a more relaxed, comfortable fit that is easier to put on and wear for extended periods. Size down for a snugger, more secure fit that stays in place better during activity. For open water swimming and watersports, a snugger fit is generally preferable to prevent the headwear from shifting during use.

Yes. TWF headwear is designed for open water and watersports use, providing thermal protection and UV coverage for beach, sea, and river swimming. Check the specific product description for details on the material, thickness, and intended use of each headwear style.

Rinse in fresh water after every use to remove salt, chlorine, and sand. Allow to dry naturally away from direct sunlight and heat. Do not tumble dry or iron. Store flat or hanging to maintain the shape of the headwear.