After creating the Jyn Erso card device I thought I'd model what I believe is an extendable baton as seen in the Rogue One teaser. Please note that the baton does not extend - this would be a nice remix for anyone up to the challenge.
The baton has a clip to mount a 12mm diameter flashlight like this one available from Fasttech.
EDIT: The baton is a tonfa! Closer inspection reveals the baton is actually a tonfa. The "flashlight" is the side folding handle. The next iterations of the baton will be geared towards making the baton spring loaded and collapsible, and the baton will deploy when the side handle is unfolded to its fighting position at right angles to the baton.
This might take a while so bear with me. If you're knowledgeable about spring loaded and trigger mechanisms please comment! It will really help me.
Thanks once again to RPF user Laubi for the excellent reference images from Nuremburg Toy Fair.