This is a bracket to let you put a flexion extruder on your CR-10. Make sure you have a pass through coupler for the bowden tube so the tube makes contact with the flexion. That is what stops the filament from bending and escaping the extruder.
this is what I use:
But any cupler that can do a pass through of the tube should work
To make sure the tube is correctly in place, you should cut an angle (60°) on the PTFE tube that goes against the Flexion drive unit. It should be pushed against the nip point with the cam on position 4.