Class 4 microprobe
A class 4 microprobe was a specific type of microprobe that was used by Starfleet during the late 24th century. The  carried these microprobes.

While inside a nucleogenic cloud being in 2371,  used a class-4 microprobe as a diversion to draw the multi-polar charges from the creature while it "sutured" the wound with nucleonic beams. The diversion was ultimately successful, as were the repairs to the creature. ()

Probes