Solid propellant rocket stage. . Used cluster of four motors with Nylon-B propellant.
Gross mass: 6,600 kg (14,500 lb). Unfuelled mass: 1,400 kg (3,000 lb). Specific impulse: 200 s. Specific impulse sea level: 200 s. Diameter: 1.70 m (5.50 ft). Span: 1.70 m (5.50 ft).