Depending on whether you go by Season Four’s “Hard Time” in which this prop was identified as a Quantum Flux Regulator Mark 3 or the Season 5 episode “Empok Nor” in which it was identified as an Optronic Coupler.
Either way it’s a prop I’ve always loved and is a key part of O’Brien’s toolkit.
It’s almost certainly Cardassian in design as it has their signature copper colouring, compared to the standard Starfleet Silver 7173 colouring.
I made a 3D model to get the proportions as close as I could from screencaps. I had the end piece 3D printed in resin which was painted Toyoyta Silver No. 2 with a clear acrylic hemisphere glued into the emitter recess.
Then cut the main body from a piece of clear acrylic tube, 3D printed the connector that joins it to the central clear acrylic that allows the LEDs to shine though with four 3D printed rings painted gold to segment the central clear acrylic tube core.
The LEDs in the central core were soldered together and connected in 3 groups of 3 that sequence down into the main body as seen in the show.
The end cap/battery access was 3D printed with a separate bobble/knob on the end painted gold.
Despite this being a tool mainly seen in DS9, some of the best close-up views were in the Voyager season 5 episode “Nothing Human” where the prop is redressed slightly as a Cardassian surgical tool being used by Krel Mocett and the EMH in a holographic recreation of Mocet’s laboratory.
“Hard Time”
“Nothing Human”
Some other shots of the prop.
A video of the prop in action.
