Adam Levine fans got an eyeful on Wednesday when his fiancée, Behati Prinsloo, posted a pic of “The Voice” mentor in his underwear!

Pic! Adam Levine in His Underwear

The caption on the hot Instagram photo read, “'70s porn called. It wants its vibe back. Immediately.”

Adam proposed to Behati (who likes posting nearly naked pics of herself on Instagram, too) in July.