Therese Alshammar was wearing a Jaked swimsuit, a European brand which uses a fabric that appears to be chloroprene in nature. The suit has few seams, an indented cut in the chest area and could provide modesty issues for swimmers.
From The Australian:
Alshammar immediately submitted an appeal against her disqualification. But after discussing the rules with referee Janelle Barnett, Alshammar elected to withdraw her appeal.
Alshammar told The Australian she had misunderstood the local swimsuit rules: "I'm still happy with the swim - it's just a technicality in my eyes.
"I have obviously not understood the rules of the Australian championships. I was wearing a unisex suit which does not cover my chest completely so I need to wear an old cut-down suit underneath. I thought it was a modesty suit. It's just so I don't fall out the side, to feel more comfortable."
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