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      Three pastel pink bubbles with sparkles and subtle iridescent highlights
      Three pastel pink bubbles with sparkles and subtle iridescent highlights
      Shark Tank studio set with five seated judges left; Hayley Segar at right with three models in black swimwear beside 'oneWith' screen.

      our shark tank journey

      our viral swimsuits made a splash on Shark Tank, Season 16 Episode 9 — and we scored a deal with two Sharks! watch on ABC.com or Hulu.

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      Shark Tank TV logo
      Shark Tank TV logo
      Shark Tank TV logo
      Shark Tank TV logo
      Shark Tank TV logo
      our must-have styles that we brought to the Tank

      Shark Tank featured items

      the magic of wearing onewith

      see it on, IRL

      Size: M

      Woman in tan bikini and straw hat sitting poolside reading a book, towel, snack and soda can beside her.

      Size: S + M

      Size: 2XL

      Woman in a black onewith bikini sitting on a beach

      Size: S + M

      Plus-size woman in a blue two-piece bikini standing beside an indoor pool.

      Size: L

      1 FREE exchange on eligible US orders

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      size inclusive (XXS-3XL)

      Two-person users icon indicating user accounts

      patented, US Patent No. 12,357,039

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      Hayley Segar, founder of onewith, smiling onstage holding a blue product, with the onewith logo visible on a screen.
      Three pastel pink bubbles with sparkles and subtle iridescent highlights

      hi! i'm hayley, founder of onewith.

      we’re so happy you discovered our swim that fits like undies on Shark Tank; welcome to whole new kind of swimsuit that is better-than-seamless, and truly onewith your body. thanks for supporting my female-founded & led small business!

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      5.0/ 5

      What people are saying

      5.0/ 5 5.0
      been searching my whole life for this
      Plus-size woman wearing a black bikini

      These are exactly what I’ve been looking for my whole life. I love the way I look in seamless underwear and always felt like I looked smushed in a regular swim bottom. This fits PERFECTLY

      Jillian M.

      Verified Buyer

      5.0/ 5 5.0
      skeptic turned fan
      alexhakim16 / M

      Was very skeptical on the fit, but these truly do feel like your no show underwear!

      Maritza R.

      Verified Buyer

      4.5/ 5 4.5
      best bottoms ever
      Woman seen from behind in black bikini top and high-cut underwear, curly hair, arms raised.

      I probably have close to 100 bathing suits and NONE have the fit that these do!! They fit like they were custom-made and don’t need adjusting every time I get out of the water!

      Amanda F.

      Verified Buyer

      5.0/ 5 5.0
      it really does fit like my underwear
      alexhakim16 / S

      My soft bits don’t spill. I’m comfortable and I look great. Exactly like my best of pair of underwear! It’s amazing

      Janet R.

      Verified Buyer

      5.0/ 5 5.0
      THEY'RE PERFECT
      ariellamayamendes / XL

      I’m obsessed, genuinely the best fitting bathing suit bottoms I’ve ever owned. Highly HIGHLY recommend! I am 5’4 ,145lbs and I got a size medium :)

      Kylie B.

      Verified Buyer

      Three women sitting on a seawall facing the water, wearing blue and black swimsuits, showing diverse body types.

      “we changed swimwear so that

      women don't feel the need to

      change themselves.”

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      back shot of model wearing onewith's woodmont bikini bottom in cove
      model wearing Bellows Plunge High-Cut One Piece in cherrydip
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      Woman in blue bikini standing on porch holding sign reading
      @onewithswim
      Woman wearing a black onewith bikini
      @itsmisslys
      Woman reclining on rocky shore in a black bikini, wearing layered gold necklaces and rings, hand on chest.
      @ahmeimae
      Woman reclining by a pool wearing a black bikini
      @traceydoes_
      Woman in a brown swimsuit top wearing a necklace and an orange hibiscus in her hair, smiling beside a potted hibiscus.
      @ivana_ferro