the m371a1 round utilizes a special fin-stabilized projectile which employs the shaped charge principle to defeat armor. it does not depend upon the warhead's velocity at the moment of impact for its effect, relying instead on the focusing effect of the shape of its explosive filler. the explosive charge collapses a conical metal liner inside the warhead into an extermely high-velocity superplastic jet. this superplastic jet is capable of penetrating steel armor to a depth of seven or more times the diameter of the explosive charge. the end of the projectile is a long and narrow stand-off of a length that allows the heat warhead to achieve maximum effect against the target.