Rocket Crafter Inc. is an engine factory using 3D addition. It has a major contract with DARPA.

-Standing out the Comet Series Hybrid engine (3D printed rocket engine). It has performed satisfactory tests. Below the STAAR-3DTM in full operation.

“Comet STAAR-3DTM”

-RCI has also built solid fuel engines like the one in the picture below.

“A Rocket Crafters solid-fuel engine”