: Based on the Apollo Lunar Module landing engine, this provides excellent stability and allows for deep throttling.
: The first to feature a regeneratively cooled nozzle and combustion chamber. It powered the first privately developed rocket to reach orbit (Falcon 1 Flight 4) and early Falcon 9 flights. Merlin 1Г—1
: An upgraded variant of the 1A with a more powerful turbine; it was never used on a flight vehicle before SpaceX shifted to regenerative cooling. : Based on the Apollo Lunar Module landing
: Uses a triple-redundant flight computer system on each engine to ensure high reliability during launch. Merlin 1Г—1