dsc71550.jpg

Decent Propulsion System engine mockup's helium injector valve ID plate. It reads

Rocketdyne
A Division of North American Aviation, Inc.
Part Name: Hel. Inj. Valve
Part No.: 557720
Sys.: Oxid.
Ser.: [blank]
Mod. No.: SE-10
Rating: 225 PSI
Insp: [blank]
Cust. Part No.: [blank]

Rocketdyne's entrant in the DPS engine competition used helium injection to accomplish deep throttling, giving additional evidence that this is likely a mockup Rocketdyne's version of the DPS engine.