Size chart

This size guide covers the Arena Powerskin Primo Women’s Open Back Racing Suit — the world’s first tensoelastic racing suit and the newest addition to the Arena Powerskin family. Made from Hyperforce fabric that powerfully compresses as it stretches, the Primo delivers explosive swimming without restriction.

The Primo’s functional design includes X-tape connecting the upper body and hips for enhanced core stability, a new more comfortable strap design, and flow channelling along the exterior surface for better hydrodynamics. Easily reach, stretch and rotate in the Primo’s open-back design — built for performance at every level. All measurements are body measurements taken directly from your body. Use your Torso Loop (D) as the primary sizing guide.

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Body Measurement Points
Arena Arena Powerskin Primo Women's body measurement points — chest, waist, hip and torso loop
How to Measure

Take all measurements directly against your skin using a soft tape measure. Use the Torso Loop (D) as the primary sizing guide — this determines how the suit sits across the shoulders and through the body.

  • A
    ChestMeasure around the fullest part of your chest, keeping the tape horizontal and snug but not tight.
  • B
    WaistMeasure at the narrowest part of your natural waist.
  • C
    HipMeasure around the fullest part of your hips and seat, keeping the tape horizontal.
  • D
    Torso LoopMeasure over one shoulder, down the front, under the crotch and back up to the same shoulder.

If measurements fall between sizes, use the Torso Loop as the primary guide. Speak to a member of staff at Allens if you are unsure.

Sizing Table — Arena Powerskin Primo Women's
Sizing 18 20 22 24 26 28 30 32 34
International Size Equivalents
UK 18 20 22 24 26 28 30 32 34
USA 18 20 22 24 26 28 30 32 34
France 24 26 28 30 32 34 36 38 40
Italy 28 30 32 34 36 38 40 42 44
Germany 22 24 26 28 30 32 34 36 38
Body Measurements (cm)
A — Chest 69–74 74–79 79–84 84–89 89–94 94–98 98–102 102–106 106–110
B — Waist 54–58 58–62 62–66 66–70 70–74 74–78 78–82 82–86 86–90
C — Hip 70–75 75–80 80–85 85–90 90–95 95–100 100–105 105–110 110–115
D — Torso Loop 116–123 125–133 136–143 146–153 156–163 166–173 171–178 176–183 181–188

All measurements are body measurements, not garment measurements. Use the Torso Loop (D) as the primary sizing guide. Speak to a member of staff at Allens if you are unsure.

Fit Notes — Arena Powerskin Primo Women's
  • Use the Torso Loop (D) as the primary sizing guide — this determines how the suit sits across the shoulders and through the body.
  • If your measurements fall between sizes, speak to a member of staff at Allens who will be happy to advise on the best fit.
  • The Hyperforce tensoelastic fabric powerfully compresses as it stretches — the suit should feel firm and energising, moving with the body rather than restricting it.
  • The X-tape connecting the upper body and hips should lie flat with no lifting or twisting — this structural element provides core stability and should remain smooth throughout the race.
  • The open-back design should sit flat across the shoulders — ensure the comfort straps are not twisted and the back panel lies smooth against the skin.
  • The flow channelling on the exterior surface should remain smooth and undistorted — any wrinkling of the outer surface indicates an incorrect fit.
  • The suit should be completely wrinkle-free when correctly fitted — any bunching or gathering indicates the suit is too large.
  • Allow 10–15 minutes to put on correctly for the first time. Take care with fingernails and jewellery to protect the fabric.
  • Do not use sunscreen, oils, or petroleum-based products before putting on the suit as these degrade the fabric.
  • Rinse in cold fresh water immediately after each use. Do not machine wash, tumble dry, iron, or dry-clean.
  • Unsure? Contact our team or call +44 1827 330600. Speak to a member of staff at Allens if you are unsure.
Frequently Asked Questions — Arena Powerskin Primo Women's

Measure your chest (A), waist (B), hip (C), and torso loop (D) using a soft tape measure directly against your skin. Use the Torso Loop as the primary guide and compare all measurements to the sizing table above. Speak to a member of staff at Allens if you are unsure.

The Torso Loop is measured by running a soft tape measure over one shoulder, down the front of the body, under the crotch, and back up to the same shoulder. This is the most important measurement for a racing suit as it determines how the suit sits across the shoulders and through the body.

If your measurements fall between two sizes, speak to a member of staff at Allens who will be happy to advise on the best fit for you. Arena racing suits are designed to fit closely — a suit that fits correctly should feel firm and supportive without restricting breathing or movement.

A tech suit should feel firm and compressive but wearable throughout a full competition day. It should be completely wrinkle-free when correctly fitted — any bunching or gathering indicates the suit is too large. The suit should feel tight but should not restrict breathing or cause pain. Seams and panels should lie flat with no rubbing or pressure points.

Arena racing suits are competition suits and are not designed for regular training use. Using a tech suit for training will degrade the fabric and reduce its lifespan significantly. Reserve it for races and competition warm-ups. Arena offer a wide range of training swimsuits for everyday pool use.

Rinse the suit in cold fresh water immediately after every use. Do not machine wash, tumble dry, iron, or dry-clean. Store flat and dry, away from direct sunlight. Avoid contact with sunscreen, oils, and petroleum-based products. Do not wring or twist the suit. Handle with care when putting on and taking off to protect the fabric.

Arena racing suit sizes (18–34) do not directly correspond to standard clothing sizes. Always use body measurements to select the correct Arena size. The international size equivalents shown in the table (France, USA/UK, Italy, Germany) are provided as a secondary reference — always prioritise body measurements.

Yes — the Arena Powerskin Primo meets FINA/World Aquatics specifications and is approved for use in all sanctioned competitive swimming events. Always check with your event organiser for any local rules regarding tech suits in competition. Speak to a member of staff at Allens if you need further guidance.

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