The technique and clothing of Roman charioteers differed significantly from those used by the Greeks. Roman drivers wrapped the reins round their waist, while the Greeks held the reins in their hands. Because of this, the Romans could not let go of the reins in a crash, so they would be dragged around the circus until they were killed or they freed themselves. In order to cut the reins and keep from being dragged in case of accident, they carried a "falx", a curved knife. They also wore helmets and other protective gear. In any given race, there might be a number of teams put up by each faction, who would cooperate to maximize their chances of victory by ganging up on opponents, forcing them out of the preferred inside track or making them lose concentration and expose themselves to accident and injury. Spectators could also play a part as there is evidence they threw lead "curse" amulets studded with nails at teams opposing their favourite.