Waist – Measure your natural waistline at or just above your belly button.
Hip – Measure around the fullest part of your hips and buttocks.
Inseam – Measure from the crotch seam down to the bottom of the leg opening.
Bust & Underbust
Bust – Measure under your arms and around the fullest part of your chest. Keep the tape level and snug, but not tight.
Underbust – Measure directly under your bust around your ribcage. Keep the tape level and snug, but not tight.
Length & Torso
Length – Measure the distance from the base of your neck down to the hemline.
Shoulder – Measure from shoulder seam to shoulder seam across the back.
Chest – Measure across the chest 1 inch below the armholes.
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Free Returns
Finally, comfortable active underwear for athletes. Biker Flex is our classic 9” inseam boxer brief in a lightweight, sweat-wicking, and supportive recycled poly fabric.
• Active underwear made for movement • 9" inseam, our longest length • Medium thigh compression • Sweat-wicking and quick-drying active knit fabric • Sleek and smooth for friction-free fit under clothing • Organic cotton gusset for breathability and hygiene
Nine inches of active coverage in sweat-wicking, recycled fabric. The Biker Flex is for women who need full thigh protection during high-movement activity — from pickleball courts to commercial kitchens to endurance runs.
9" inseam — full mid-thigh coverage; complete chafe elimination during running and cycling
Sweat-wicking, quick-dry active fabric — pulls moisture away from skin; dries fast between active sets
Recycled poly construction — sustainably made; structured for athletic performance
Medium thigh compression — holds the inseam in place through continuous high-movement activity
No roll-up — stays at mid-thigh through sprints, lunges, and lateral movements
Sleek under work pants — smooth enough to wear under restaurant or kitchen uniform pants without bulk
Organic cotton gusset — breathable natural fiber for all-shift wear
Size-inclusive — XS to 4XL
Flex Active
88% RECYCLED POLYESTER, 12% ELASTANE
Knit from OEKO-TEX certified recycled polyester and spandex, Flex fabric is for athletes who need freedom of movement. Extremely lightweight and sweat-wicking, it feels silky smooth and friction-free under clothing. With a medium compressive fit, Flex fabric is here to empower your best performance.
Softness
Weight
Stretch
Breathability
Softness
Weight
Stretch
Breathability
88% RECYCLED POLYESTER, 12% ELASTANE
Knit from OEKO-TEX certified recycled polyester and spandex, Flex fabric is for athletes who need freedom of movement. Extremely lightweight and sweat-wicking, it feels silky smooth and friction-free under clothing. With a medium compressive fit, Flex fabric is here to empower your best performance.
Machine wash cold
tumble dry low
OEKO-TEX® Certified
No-dig waistband
Wedgie free
Anti chafing
OEKO-TEX® Certified
Finally, comfortable active underwear for athletes. Biker Flex is our classic 9” inseam boxer brief in a lightweight, sweat-wicking, and supportive recycled poly fabric.
• Active underwear made for movement
• Made with recycled fabrics
• 9" inseam, our longest length
• Medium thigh compression
• Sweat-wicking and quick-drying active knit fabric
• Sleek and smooth for friction-free fit under clothing
• Organic cotton gusset for breathability and hygiene
Finally, comfortable active underwear for athletes. Biker Flex is our classic 9” inseam boxer brief in a lightweight, sweat-wicking, and supportive recycled poly fabric.
• Active underwear made for movement • 9" inseam, our longest length • Medium thigh compression • Sweat-wicking and quick-drying active knit fabric • Sleek and smooth for friction-free fit under clothing • Organic cotton gusset for breathability and hygiene
Finally, comfortable active underwear for athletes. Biker Flex is our classic 9” inseam boxer brief in a lightweight, sweat-wicking, and supportive recycled poly fabric.
• Active underwear made for movement • 9" inseam, our longest length • Medium thigh compression • Sweat-wicking and quick-drying active knit fabric • Sleek and smooth for friction-free fit under clothing • Organic cotton gusset for breathability and hygiene
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