The mercenary vessel had a crew complement of at least eight. It was equipped with warp drive and a transporter. In 2369, Seven of the crew boarded the USS Enterprise-D posing as maintenance workers from Arkaria Base. Kelsey's starship was scheduled to arrive and leave the system around the time the baryon sweep of the Enterprise was completed.
The crew of the mercenary ship stole trilithium resin from the warp core of the Enterprise, planning to sell it to terrorists. The pilot, Kelsey and the ship were destroyed, when the trilithium resin exploded on board, while the ship attempted to go to warp. The rest of the ship's crew died on board the Enterprise. (TNG: "Starship Mine")