Alexios Magnetic Armour, named after it's inventor, Tymon Alexios, is a Hoplite-style magnetic armour capable of reflecting bullets and other metal weaponry. It is extremley expensive to manufacture however, and is rarely used, mainly only worn by the New Greek Senate.
While it doesn't usually actually stop bullets completley before reaching the wearer's body, it does slow down the projectile enough to protect the wearer from significant damage.