Portumac Vader Question?

[nightrider]

Hi guys, I just got a Portumac ROTS helmet and I would like to know how others who have this helmet secure the dome. Mine has a threaded bar that goes into the top of the face mask and I was thinking of trying to find a fly nut to put on it. I plan on useing it for costuming so I need the dome to be secure, any suggestions?

Chris