In American football, "12 personnel" refers to an offensive formation featuring one running back and two tight ends. When coupled with a "wing slot offset", it means one tight end is lined up slightly outside the tackle box (wing) and another receiver lines up inside the #2 receiver position (slot). The wing and the slot receiver may be offset. This formation offers a balance between running and passing capabilities, allowing for various blocking schemes and route combinations. It can be challenging for defenses to predict the offense's intentions due to its versatility.