Fans were surprised when Michelle Williams and Amanda Seyfried, who usually wear high-fashion designers like Chanel and Prabal Gurung, stepped out in designs by H&M recently.

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But now, we learn that the store, known for its fashionable yet affordable garb, is launching a collection next month and will include both Seyfried's turquoise shorts and matching blazer and Williams' chic black and white column dress.

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Called "Exclusive Conscious," the designs will be made from sustainable materials, like organic cotton and hemp, and will boast a variety of eye-popping looks.

The line is scheduled to go on sale at H&M stores and on around April 12.

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Exclusive Conscious follows in the footsteps of the just-released Marni x H&M, the store's most recent designer collaboration, which drew in hoards of fashionistas on its March 8 launch.

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