This part is from Stockalike Realism Overhaul
cost:
390
mass:
0.5
category:
Engine
TechRequired:
advRocketry
engine_data:
standard
{"isp"=>{"vac"=>495.0, "atmo"=>340.0}, "propellant_ratios"=>{"LiquidHydrogen"=>5.0, "LiquidOx"=>1.0}, "max_thrust"=>35.0}