UNB have revealed more concept teaser images for their upcoming release "Black Heart".

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UNB revealed a cool, blue tone in their previous teasers, and for their latest teasers, the group heated things up with an orange hue. 'The Unit' project group will be making a comeback with their 2nd mini album 'Black Heart', which releases on June 28 KST.

Check out UNB's latest teaser images below!