Class-6 probe

A class-6 probe or more specifically class VI communications link and emergency buoy was a type of probe used by the Federation Starfleet in the 24th century.

The probes were essentially modified class-3 probes and had a range of 4.3x1010 kilometers. They were powered by a micro fusion engine which could propel them at warp 0.8. 

In addition to standard sensors, these probes had a radio- and subspace-transceiver capable of transmitting at 350 megawatt and expanded deuterium storage to power the transceiver and adjust their orbit.