When it comes to menstruation, we don’t talk about it enough. Period. Which is why Thinx – who make those period-absorbing knickers you may have read about – has launched the first Selfridges window dedicated to menstruation.

The aim – apart from selling more pants, we presume – is to break taboos and encourage a more honest conversation. “We’re not here to tell people to love their period,” Thinx design director, Meng Shui, tells HufPost UK. “We’re here to support them when they don’t feel so great about their periods.”

The menstruation-themed window display will fill the iconic Oxford Street windows for two weeks – a spot typically reserved for luxury handbags and high fashion – and we can guarantee people will have something to say. While period pants may still be a luxury item for some, others think of them as life-changing. 

[Read More: We Tried Period Pants And Got Brutally Honest About The Experience]

The installation, which features a red balloon squashed in between two concrete blocks, is more conceptual than literal – perhaps disappointingly so. But then, Selfridges is known for its artistic displays, so maybe a bucket of actual period blood wouldn’t have felt quite right.

The upper concrete beam represents the anxiety people feel about their period, apparently, because the red balloon (ie. your period) could burst at any moment and you could leak everywhere – while the post that prevents the block from squashing the balloon is covered in period-proof Thinx underwear. “Liberate yourself / Welcome your release, secure / We’ve got you covered,” reads the window text. So far, so (kind of) symbolic – when we visit, there are already lots of influencers eagerly snapping pictures for their Instagram feeds.

The window, which took two months to create from conception to today’s unveiling, draws inspiration from abstract artists such as Salvador Dali and Alicja Kwade, who is currently exhibiting at The Met in New York and whose work is about “tension, suspense and balancing”.

Meng Shui says the team is constantly looking to contemporary art to spark their ideas. Whether passers-by will get the message – especially given there’s no mention of the words period or menstruation anywhere – is another matter.

Marci Dollinger, 54, and her daughter Shayna, 19, from San Francisco stop in front of Selfridges. They’ve not heard of Thinx – and are struggling to decode the window. “I like the idea of it,” Shayna says, when I explain the campaign to her. “And I think I would try it out but I don’t know how effective it would be. It feels very esoteric… I wouldn’t get the concept unless it was written out.”

But will it start a conversation about periods? “I think so,” says Marci. “We’ve just come from Africa and they are doing a reusable pad there and the same conversations are coming up. I think it’s an important conversation, especially for young women to have – to not be embarrassed by it. It will make men way more uncomfortable than women to see that there.” 

Keeanea Morgan, 23, a graphic designer, is more persuaded. “I think the colour of the ball says it all. And the words. Once you actually stop you know this is what’s it is really about,” she says.

[Read More: Why Is There Plastic In Tampons?]

Thinx’s chief brand officer Siobhán Lonergan calls the display an “abstract visualisation of the challenges and chaos associated with periods” – and the relief of putting on a pair of Thinx. “Periods often come with pain and discomfort, not to mention leak-anxiety that can feel like a heavy weight,” she says. “Thinx are a simple, innovative solution that help relieve emotional pressure while providing physical comfort and support.”

Big, functional period pants hung out to dry in the polished windows of a luxury department store – is this a sign the conversation around menstruation is changing, even drip by drip? Well, every little helps. But Thinx don’t come cheap, nor are they the only period pants on the market – you can read our honest reviews of four brands here, as tested by writers with different flows.

In the US, where Thinx HQ is based, the team do a lot of advocacy work to campaign for free, easy access to period products, working with youth-led NGO Period. As for supporting UK initiatives, where period poverty is high on the agenda – they’re working on it, they say, so watch this space. Primary and secondary school pupils will now get free tampons and sanitary towels, the government recently announced – but with a younger generation ever more concerned about the environment, is the next step period knickers for all?

Selfridges Oxford Street stocks Thinx period-proof underwear in its Body Studio on the third floor, sold in hiphugger, high waist, sport, boyshort, thong, cotton brief and bikini cuts, from £21 to £35. Thinx are also available on Asos and in Boots, Covent Garden.