a latching relay employing an electro - magnetic relay coil having associated therewith opposite end armatures . this relay coil receives operating power by way of an input contact member . one of the armatures carries a manually operated switch which also includes an end for actuating the closure contact . the opposite armature functions to assist in the manual switching and in its inactive state blocks operation of the primary armature . another contact is associated with one of the armatures for providing high power transfer .