Designer: Rocketdyne. Used on stages: Saturn MS-II-1-J-2T-200K. Used on launch vehicles: Saturn MLV-V-1/J-2T/200K. Propellants: Lox/LH2Thrust(vac): 90,686 kgf. Thrust(vac): 889.30 kN. Isp: 435 sec. Isp (sea level): 300 sec. Burn time: 429 sec. Diameter: 2.5 m. Length: 1.3 m. Chambers: 1. Country: USA. Status: Study NASA 1966. Comments: Proposed for later versions of Saturn V. Toroidal aerospike plug nozzle version of J-2.