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Dayno One Piece Swimsuit

Color:
Size:
Size Chart

One Piece Swimsuit
Size Guide

Torso measurement is most important for finding your accurate one piece size.

If you are in between torso measurements or know your torso runs long we recommend sizing up!

Measurement Guide

Torso

The most important for finding your accurate one piece size

Measure from the top of your shoulder over the fullest part of your bust, through your legs and around, up your back to the starting point.

If you are in between torse measurements or know your torso runs long, we recommend sizing up!

Bust

Measure around the fullest part at the bust.

Waist

Measure around the smallest part of the waist.

Hips

Keep measuring tape parallel to the floor and measure around the fullest part of the hip.

Jolyn swimwear, a woman with measurement arrows and guide

Fit Questions

If you want a second opinion or need help figuring out your size, reach out to us at contact@jolyn.com and we’ll sort you out!

Free shipping on orders $90+!

Details

 

Our latest version of our bestselling Dayno tie-back training onesie is updated with a lengthened torso for more comfortable coverage, as well a scooped neckline for an even flatter fit when in streamline position. The suit's adjustable tie-straps give you the perfect fit for the moment—loose for comfort or snug for speed. Our insanely durable fabric stretches along the length of the body for easy movin’ during any aquatic activity. 

 Features:

  • Good for: Swimming, water polo, lifeguarding, paddling, ocean and pool activities
  • Tie-back 
  • Medium coverage
  • Coverage 3
  • Unpadded
  • Lined for maximum privacy
  • Tagless for maximum comfort
  • Chlorine proof
  • 2-way stretch
  • Reinforced stitching

Fabric Composition:

Care Instructions:

  • Hand wash cold
  • Hang dry
  • Do not iron, dry clean or bleach 

 

JOLYN does not recommend tie straps to be used in racing or FINA sanctioned events. Fastening systems including ties are not allowed in competition, as per FINA regulations.

How to Measure Yourself

Shipping & Returns

Read our full return policy here.

Domestic Shipping:

  • Free standard shipping on orders $90+!

  • Standard shipping takes about 5 - 7 business days.

  • Holiday Standard Shipping: Order by 12/14 for the best chance of receiving your package by 12/25.

  • Holiday Express Shipping: Order by 12/20 for the best chance of receiving your package by 12/25.

  • Extended Returns: Items purchased between Nov 1, 2025 and Dec 20, 2025 can be returned until Jan 31, 2026.

International Shipping:

  • Allow one business day for order processing.

  • Standard shipping takes about 12 business days, depending on destination and selected shipping method. The estimated transit time is presented at checkout.

  • For Canada, duties and taxes will be calculated at checkout.

  • For Australia and United Kingdom, taxes are included in the price and duties will be calculated at checkout.

JOLYNSIDER Rewards

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Features

  • High impact

    High impact

    Made for the highest level of activity

  • Foreverever Fabric

    Foreverever Fabric

    Our classic bestselling fabric loved by athletes for its durability

  • Medium Coverage

    Medium Coverage

    Sits diagonally across the bum

  • UPF 50+

    UPF 50+

    Stay protected during long days in sun


JOLYNSIDER REWARDS

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