An injection molding apparatus comprising a clamp plate, a heated manifold, an actuator, a mold and a cooling device, wherein the cooling device comprises: a heat transmitter comprising a distal arm or member and a proximal base or member, the distal arm or member being mounted by a spring loadable interconnection or engagement to or with the proximal base or member, the clamp plate, the mold, the manifold, the actuator and the heat transmitter being assemblable together in an arrangement wherein the spring loadable interconnection is loaded urging the distal end surface of the distal arm or member into compressed engagement with the clamp plate.