She decided to have the operation after losing both her mum and sister to breast cancer.
Newsbeat's been charting her progress over the last few months and Claira tells us she's doing really well.
The 27-year-old carries the BRCA 1 gene which gives her an 85% life chance of also getting the disease.
"I feel great," she says.
"I've stopped taking pain killers and I'm super pleased with my new boobs."
"I've recovered faster than I expected, my boobs look better than I expected and I was in far less pain than I expected."
"Going into this I tried my hardest not to have too many expectations and certainly not to focus on them," she explains.
"I always knew that whatever happened during that operation and indeed after it I would deal with as and when it happened.
"I focused on how lucky I was to be in the situation I was in, to know what I know and that I was able to do something about it.
"This experience has been one of huge personal growth for me," she says.
"It has challenged and changed a lot of what I thought I knew about myself and my life," she goes on.
"I can only describe the whole experience as life-changing in the best possible way. I'm happier than I have ever been.
"I want everyone reading this to understand that your personal happiness is in your hands."
She feels huge gratitude to those who looked after her: "I want to say thank-you to surgeon, Tibor Kovas, and his team at Guy's Hospital for doing such a great job.
"My journey doesn't end here, it starts," she says.
"I will be working more with the charities Genesis and Breakthrough Breast Cancer to raise money, awareness and to help women who are planning the same procedure," she ends.
Claira will be the focus of a documentary for BBC Radio 1 Stories, due to be broadcast later this month.
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1Xtra DJ, Claira Hermet, had a double mastectomy a few weeks ago.