Micro-power relayedit this page

From Memory Alpha, the free Star Trek reference

A micro-power relay was a piece of technology used in maintaining and repairing damage to a starship's warp core.

When the warp core matrix compositor of the USS Malinche became fused after being attacked by a booby-trapped Cardassian freighter and three Maquis raiders, Captain Sisko beamed a damage control team to the Malinche with 12 micro-power relays to assist Captain Sanders with repairs. (DS9: "For the Uniform")