Name: OPEN-BACK SLEEVELESS SHIRT
Brand: COS
SKU: 1239289001
Price: 55 EUR
Availability: InStock

SALE: 200+ NEW PIECES ADDED & FURTHER REDUCTIONS

Newslettersubscribe

Gift Card

Delivery Methods

Returns

Contact Info

Women

Sale

SALE: 200+ NEW PIECES ADDED

New Arrivals

Cashmere Knitwear

Cashmere

SALE: FURTHER REDUCTIONS

Knitwear

Make sure that your favourite items remain long-loved pieces for years to come; read our 

For information relating to environmental qualities or characteristics of this product, you can find

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 pressurised 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.

Delivery

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

Questions?

We hope you will love everything that you order from us but if something isn't quite right, you have 30 days to send it back to us.

Please note any purchase made online, from 5th November 2025 - 10th December 2025 can be returned up until 9th January 2026. For purchases made from 11th December 2025 onwards, our normal returns policy will apply.

We'll give you a refund by the same method you used to pay, minus a returns processing fee of €3 within 14 days of your return. We ask that items are returned clean, unworn and have all their tags on.

Please note that items bought online cannot be refunded or exchanged in any of our stores. Certain pieces may not be returned for hygiene reasons.

We hope you will love everything that you order from us but if something isn't quite right, you have 30 days to send it back to us.

We'll give you a refund by the same method you used to pay, minus a returns processing fee of €3 within 14 days of your return. We ask that items are returned clean, unworn and have all their tags on.

Please refer to our returns page for more information.

MEMBERS RECEIVE FREE SHIPPING WITH A MINIMUM SPEND OF {{currencySymbol}}50

GET YOUR GIFTS IN TIME: ORDER BY MIDDAY ON DD/MM/2025

This label is used to inform the carrier that the package contains flammable substances and has special transportation requirements.

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.

We have added this information due to new EU regulations and to give our customers greater transparency about how product prices change over time. Under EU price display regulations, any announced price reduction must indicate the lowest price for a product in the last 30 days – we refer to this as 'lowest historical price'.

The COS womenswear team play with unexpected silhouettes for this season's directional shirting. Cut from crisp white cotton-poplin, this sleeveless version has classic features on the front, from the pointed collar to the buttoned placket. Turn to the back and you'll find a dramatic open detail that overlaps at the nape.&nbsp;&nbsp;Relaxed fitButton closure&nbsp;Shell: 100% Cotton. Excluding trims / Machine wash&nbsp;Back length of size XS/S is 73cm / Model wears a size XS/S

The COS womenswear team play with unexpected silhouettes for this season's directional shirting. Cut from crisp white cotton-poplin, this sleeveless version has classic features on the front, from the pointed collar to the buttoned placket. Turn to the back and you'll find a dramatic open detail that overlaps at the nape.&nbsp;&nbsp;<ul><li>Relaxed fit</li><li>Button closure</li></ul>&nbsp;Shell: 100% Cotton. Excluding trims / Machine wash&nbsp;Back length of size XS/S is 73cm / Model wears a size XS/S

XS/S

OPEN-BACK SLEEVELESS SHIRT

The COS womenswear team play with unexpected silhouettes for this season's directional shirting. Cut from crisp white cotton-poplin, this sleeveless version has classic features on the front, from the pointed collar to the buttoned placket. Turn to the back and you'll find a dramatic open detail that overlaps at the nape.&nbsp;&nbsp;<ul><li>Relaxed fit</li><li>Button closure</li></ul>&nbsp;Shell: 100% Cotton. Excluding trims / Machine wash&nbsp;Back length of size XS/S is 73cm / Model wears a size XS/S

White

Product contains at least 0% recycled materials.

Product contains at least 76.99% recycled materials

We've updated our sizes based on your feedback. Please refer to the size guide.

Women's ready to wear tops

Womens Tops, Shirts & Blouses

Sign up to receive 10% off your first order and find out first about new collections, events and exclusive offers.

THE COS NEWSLETTER

About Us

https://career.cos.com/content/coscareer/en_gb.html

https://press.cos.com/content/cospress/en/home.html

Store Locator

Sustainability

Features

https://www.facebook.com/cos/

https://www.instagram.com/cosstores/

https://uk.pinterest.com/cos/

https://www.tiktok.com/@cos

https://open.spotify.com/playlist/03xISbDqJQ1DYgqtR9cjmN

THE COMPANY

Payment

Product Care

Size Guide

Fit Guide

Student Discount

ASSISTANCE

Privacy Notice

Terms And Conditions

Terms Of Service

Cookie Notice

Accessibility Statement

LEGAL

Reviews Terms and Conditions 

Shopping Bag

Members receive free shipping with a minimum spend of {{currencySymbol}}50.

Favourites

You are currently shopping on {{currentCountry}} website. When changing countries your shopping bag will be emptied. Are you sure you want to proceed?

CONFIRM YOUR SHIPPING LOCATION

It looks like you are based in {{currentCountry}} but are about to switch your shipping location to {{targetCountry}}. Would you like to continue?

Thank you for signing up to the COS newsletter. We’ve just sent you a confirmation email – please check your inbox and click the link to confirm your subscription.

Confirm your subscription

We were not able to confirm your subscription. Please click below and we will resend a confirmation email.

Something went wrong

Thank you for being with us, if you experience any problem with your subscription contact our support.

You are already a subscriber

We will keep you up to date on new collections, events and promotions.

Thank you, you are now subscribed

I would like to receive personalised promotions from COS a brand of the H&M Group. I confirm that I’m 16 years or older. I consent to let H&M Group process my personal data to provide me with personalised email in accordance with the 

I would like to receive personalized promotions from COS a brand of the H&amp;M Group. I confirm that I’m 16 years or older. I consent to let H&amp;M Group process my personal data to provide me with personalized email and text messages in accordance with the <a href="/en-eu/customer-service/privacy-notice" uuid="d35a6d87-cf86-4052-b79a-3c4d61265a7e" target="_self">privacy notice</a>.

Sign up for 10% off your first order

Thank you, we have updated your subscription preference accordingly. Please note that it may take a day or two for the system to update and you may receive newsletters during this time that were already on their way to you. If you have any concerns, please get in touch by phone on +61 1800 960 831 or email us.By unsubscribing, we will no longer send you updates about new products, personal recommendations and sales to the email linked to this newsletter.

YOUR SUBSCRIPTION IS UPDATED

I would like to receive personalised promotions from COS a brand of the H&M Group via email and text messages. I can withdraw this consent at any time. I confirm that I'm 16 years old or older. I acknowledge that my personal data will be processed by H&M Group in accordance with the 

You are now subscribed and we will keep you up to date on new collections, events and promotions.

Africa

Asia

Europe

Middle East

North & South America

Oceania

Personal Info

Microsoft.Targeting

Turns on / off additional Material Information in PDP drawer

Azure Insights Telemetry for nextjs, both frontend and backend

Turning this on will allow an Inactivity trigger (when user is returning) for an extra selection call to Centra

Enables the Ingrid delivery address locking functionality in checkout, which allows the delivery address section to be locked to prevent changes.

Used to to display debug info from components using <Debugger> - Prod here is irrelevant as it can only be featureflag toggled for lowe environents

FeatureFlag that is determines ReviewsDrawer Version

Feature Flag to enable/disable reviews functionality in My Account application area.

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

Flag that enables Digital Order Return feature
- Link Button on My Account Order History
- Order Return Block on different pages

Controls if PDP delivery and returns sidebar shows Ingrid delivery estimation time widget or content from Storyblok.

Disable preorder on lower environments. Preorder cannot be disabled on PROD.

testflag to show debugger in action provided clientDebugOverlay flag also is avalilable. Will never work in Production (only limited to lower Environments)

[Deprecated] Flag that will enable the use of the new elevated components as part of the Elevation project.

Used to enable/disable the option for overriding the navbars sticky behaviour in page settings.

Flag that will enable the use of the new elevated footer as part of the Elevation project.

Flag that will enable the use of the new elevated navigation as part of the Elevation project.

FF for elevated size select buttons/selector

Controls display of elevated quickshop drawer

Enables browser-based API mocking using MSW (Mock Service Worker) for local development, testing, and preview environments. When active, network requests are intercepted and served with mock data, improving frontend development speed and reliability. Disable in production.

Enabled PDP stock check call caching. Cache control headers will be set to 1 min.

Enables the new Wishlist API service as the storage backend. When this flag is true, the app persists and reads wishlists via the backend service.  When false, it uses the client-side cookie storage.

When enabled it doubles PDP revalidation and caching time (will be set to 20 mins)

When enabled it doubles PLP revalidation and caching time (will be set to 20 mins)

This feature flag can be used to toggle support for faceted navigation on PLPs.

Allow COS App to use FHR AB Test caching instead of directly passing sessionID.

Controls whether Klarna payment options are displayed as separate, selectable payment categories or as a single consolidated payment method.

Purpose: Enables historical price display for products to meet regulatory compliance requirements. 
What it does: When enabled, shows the previous price alongside the current price for applicable products, allowing customers to see price changes over time. 
Why it exists: Satisfies consumer protection regulations requiring transparent pricing history, helping customers make informed purchasing decisions and compare price trends.

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).
Why it exists: Satisfies consumer protection regulations requiring transparent unit pricing to help customers compare products sold in different quantities.

Our new Product Details Drawer using tabs 

Will trigger extra attention around size-guide, a red-text-button that animates, and notification messages in Wishlist and in the opend size-guide drawers

If enabled, the Storyblok Cache service endpoint will be used to proxy Storyblok requests. Note: Not all envs have the endpoint configured so may not affect them.

Flag to enable test countries.
As of today (2024-07-19) these are:
BE, CY, GR, HR, LU, PT

Flag to enable test markets. 
As of today (2024-07-12) these are: 
CH, ES, FR, GB, IE, IT, NO, PL, SE

This flag is for new turbo cookie compliance

Use Upper Case (instead of lower / sentence case) in the product Card Titles