Abstract: 1. A voltage-gradient sensitive proximity fuze for use with a rotating prctile against electrostatically charged targets and which will detonate the projectile at an optimum distance from the target comprising: p1 (a) a pair of conducting electrostatic probes, said electrostatic probes being arranged symmetrically with respect to a plane of symmetry containing the longitudinal center axis of the projectile, said probes being of such limited circumferential extent that a voltage-gradient is developed between said probes when the longitudinal center axis of the projectile is at an angle to an external electrostatic field, whereby the fuze will have a high voltage-gradient sensitivity in a direction transverse to said longitudinal center axis;(b) a voltage sensitive electronic firing circuit, said pair of conducting electrostatic probes connected to said circuit to cause said circuit to detonate said projectile when the voltage difference between said probes exceeds a predetermined amount.