Name: THE OPEN-BACK MAXI DRESS
Brand: COS
SKU: 1242185001
Price: 165 USD
Availability: OutOfStock
Rating: 3 (1 reviews)

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Product sheet relating to environmental qualities or characteristics

We are really pleased to offer you a great range of fashion with a wide selection of cosmetics. However, a few of our cosmetics contain flammable substances and therefore have delivery restrictions. Eg. nail polish, certain perfumes and nail polish removers as well as pressurized spray cans. At the same time, all our beauty items are tested to ensure that they are safe to use. It's only if you wish to return or exchange items containing flammable substances that you need to be aware that there are special transportation requirements.

We deliver to all states including P.O. boxes, but we are unable to ship APO/FPO/DPO addresses or US Territories.

Some fragrance products are classed as dangerous goods and therefore cannot be delivered to the below locations:

4-7 business days. Orders placed Monday–Friday will be delivered within 4–7 business days. Orders are delivered Monday–Saturday to residential and commercial addresses.

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 3-5 business days. Orders placed Monday–Friday will be delivered within 3–5 business days. Orders are delivered Monday–Saturday to residential addresses and commercial addresses.

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This item cannot be returned as it is part of final sale

Please read our [frequently asked questions](/en-us/customer-service/faq/).

Questions?

We’ve extended our returns period over the festive season to offer more flexibility when you shop online. Any orders placed between November 1, 2025, and December 24, 2025, can be returned up to and including January 31, 2026. 

We hope you will love everything that you order from us but if something isn’t quite right, you have 30 days from the purchase date to return any full-price item(s) and 14 days from the delivery date to return any sale item(s) that are not marked 'Final Sale' for a full refund to the original payment method for the order. We ask that items are returned clean, unworn and have all their tags on.

A $5 return fee will be deducted from your refund should you choose to use the prepaid label included with your order.

We hope you will love everything that you order from us but if something isn’t quite right, you have 30 days from the purchase date to return any full-price item(s) and 14 days from the delivery date to return any sale item(s) that are not marked 'Final Sale' for a full refund to the original payment method for the order. We ask that items are returned clean, unworn and have all their tags on.

A $5 return fee will be deducted from your refund should you choose to use the prepaid label included with your order.



Please refer to our [returns](/en-us/customer-service/returns) page for more information.

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HOW TO MEASURE GARMENT

It's just as easy to return a nail polish as it is to return a pair of jeans.

The easiest way to return any beauty product classified as dangerous goods is to use the original parcel because it already has the LQ.

Dangerous goods label (pictured below). Just make sure to fill the box with paper or filler so the product will stay in place.

This piece is part of the ATELIER capsule; an exploration of the modern wardrobe, founded on the principles of luxury and exceptional design. CUTRedefining eveningwear codes, this floor-length dress is a striking way to mark the occasion. It's shaped with a rounded neckline, open back and a hooked grosgrain strap that frames the shoulders. A pair of knotted ties cascades from the back of the dress down to the hem, creating a sense of movement as you walk. CLOTHThis paneled piece is crafted from recycled-polyester satin that lends fluidity and an effortless drape. It's offered in a refined color-blocked palette of carbon, champagne and pearl. CRAFTConsidered touches include the concealed zip closure, adjustable grosgrain bra straps and laser-cut edges for a light, clean finish. Shell: 100% Recycled polyester. Excluding trims / Machine wash Back length of size 6 is 42.71&quot; / Model wears a size 6

This piece is part of the ATELIER capsule; an exploration of the modern wardrobe, founded on the principles of luxury and exceptional design. CUTRedefining eveningwear codes, this floor-length dress is a striking way to mark the occasion. It's shaped with a rounded neckline, open back and a hooked grosgrain strap that frames the shoulders. A pair of knotted ties cascades from the back of the dress down to the hem, creating a sense of movement as you walk. CLOTHThis paneled piece is crafted from recycled-polyester satin that lends fluidity and an effortless drape. It's offered in a refined color-blocked palette of carbon, champagne and pearl. CRAFTConsidered touches include the concealed zip closure, adjustable grosgrain bra straps and laser-cut edges for a light, clean finish. Shell: 100% Recycled polyester. Excluding trims / Machine wash Back length of size 6 is 42.71&quot; / Model wears a size 6

THE OPEN-BACK MAXI DRESS

This piece is part of the ATELIER capsule; an exploration of the modern wardrobe, founded on the principles of luxury and exceptional design. CUTRedefining eveningwear codes, this floor-length dress is a striking way to mark the occasion. It's shaped with a rounded neckline, open back and a hooked grosgrain strap that frames the shoulders. A pair of knotted ties cascades from the back of the dress down to the hem, creating a sense of movement as you walk. CLOTHThis paneled piece is crafted from recycled-polyester satin that lends fluidity and an effortless drape. It's offered in a refined color-blocked palette of carbon, champagne and pearl. CRAFTConsidered touches include the concealed zip closure, adjustable grosgrain bra straps and laser-cut edges for a light, clean finish. Shell: 100% Recycled polyester. Excluding trims / Machine wash Back length of size 6 is 42.71&quot; / Model wears a size 6

This piece is part of the ATELIER capsule; an exploration of the modern wardrobe, founded on the principles of luxury and exceptional design. CUTRedefining eveningwear codes, this floor-length dress is a striking way to mark the occasion. It's shaped with a rounded neckline, open back and a hooked grosgrain strap that frames the shoulders. A pair of knotted ties cascades from the back of the dress down to the hem, creating a sense of movement as you walk. CLOTHThis paneled piece is crafted from recycled-polyester satin that lends fluidity and an effortless drape. It's offered in a refined color-blocked palette of carbon, champagne and pearl. CRAFTConsidered touches include the concealed zip closure, adjustable grosgrain bra straps and laser-cut edges for a light, clean finish. Shell: 100% Recycled polyester. Excluding trims / Machine wash Back length of size 6 is 42.17&quot; / Model wears a size 6

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Polyester is a synthetic fibre made from crude oil (a fossil resource).

We've updated our S,M and L sizes based on your feedback. Please refer to the size guide.

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Please note, stock levels may vary. For further information, please contact the store.

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Merchandise purchased online at a discount of 50% off or more is considered Final Sale. Items purchased as Final Sale are not eligible for return, exchange or credit without exception and merchandise is sold as is.

We hope you will love everything that you order from us but if something isn’t quite right, you have 30 days from the purchase date to return any full-price item(s) and 14 days from the delivery date to return any sale item(s) that are not marked 'Final Sale' for a full refund to the original payment method for the order. We ask that items are returned clean, unworn and have all their tags on.




Any questions? Please visit our [returns](https://www.cos.com/en-us/customer-service/returns) page. 


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Turns on / off additional Material Information in PDP drawer

When enabled, it monkey-patches the Adyen SDK's Drop-in component to intercept payment method selections and reads it back on the checkout success page to show the human-readable payment method name.

Enables automatic logout for authenticated users when changing countries to prevent cross-market session issues.

Azure Insights Telemetry for nextjs, both frontend and backend

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Controls whether Canada (CA) market is included in hreflang meta tags for SEO.

Default: false (disabled)

Behavior:
Disabled (default): Canada is excluded from hreflang tags. Use this during the initial Canada launch phase when only a landing page is available and all other pages redirect.
Enabled: Canada is included in hreflang tags alongside other production markets. Enable this once Canada has full page coverage and no longer redirects users to a landing page.

Use case: Prevents search engines from indexing Canada-specific hreflang alternates until the market is fully launched with complete page support.

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coming soon feature flag is to enable/disable the feature.

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worked together with clientDegubOverlay to display data around how long since last interactivity

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When enabled, uses the ParcelLab test country code (xt) instead of the actual user country code for the Digital Returns widget.

https://hmgroup.atlassian.net/browse/PBCDE-12822

https://hmgroup.atlassian.net/browse/PBCDE-9156

Purpose: Enables unit pricing display for multipack products to meet regulatory compliance requirements.
What it does: When enabled, displays the calculated price per individual item for multipack products (e.g., "£5 / piece" for a £10 two-pack).
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Our new Product Details Drawer using tabs 

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Flag to enable test countries.
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