Invincible Stringer in Grey – Men's Racerback Tank Top With Spartan Print The 'Invincible' stringer is a sleeveless men's tank top in a classic racerback cut, made from 100% cotton at 200 gsm. The marled grey fabric carries a black Spartan helmet framed by two large Gs, with an 'Invincible' banner underneath. Narrow straps, a deep back an...