ODN recoupler

An ODN recoupler was a 24th century engineering tool that was utilized in the repair of an optical data network.

After spending twenty subjective years in an Argrathi prison, Miles O'Brien worked with Jake Sisko in retraining his engineering skills, so as to not embarrass himself in front of the repair crews, by reviewing various engineering tools in the cargo bay.

Among the tools he recognized were the interphasic coil spanner, the ODN recoupler, and with a bit more difficulty, the quantum flux regulator, Mark III. 

When Rom attempted to disable Terok Nor's deflector array, and prevent Damar from successfully taking down the minefield blocking the Bajoran wormhole, he needed to cut power to the computer via access to the central core. In the final steps of the process he needed to decouple the ODN relays, which required the use an ODN recoupler.