Two low-mass, linear throttling, high-efficiency, leak-proof cryogenic valves of diameters 1/2" and 4" will be built and tested. Based upon cryogenically-proven Venturi Off-Set Technology (VOST) the valve has no stem-actuator, few moving parts, and an overall cylindrical shape. The valve geometry will help reduce launch vehicle complexity and facilitate assembly and testing. Reliability and safety will be enhanced due to the inherent simplicity and leak-proof design of the VOST valve. Potential NASA uses include launch, descent, and extraterrestrial use. Ground-based embodiments will benefit from enhanced thermal performance which will reduce recurring costs. Non-NASA uses include military and civilian aircraft, chemically corrosive industrial environments, superconductivity and medical applications.