Abstract: A single-actuation, synchronous dual closure disc brake device includes a mounting plate installed onto a fork leg, a U-shaped movable caliper base movably attached to the mounting plate and having an anti-rotation check opening, and a brake cable capable of being pulled and released to actuate a bidirectional, thrust cylinder driver. The thrust cylinder driver is ensleeved within the anti-rotation check hole in the center section of the mounting plate and reciprocally moves an inner motion guide sleeve and an outer motion guide sleeve. Such movement brings inner and outer brake pads into the inner and outer motion guide sleeves double-sided and opposing clamping of a brake disc.