Late in the last century, the advances in palletized weapon systems saw freighters and even passenger vessels take on roles that would have earlier required purpose built ships of substantial tonnage. While initially for self protection (in view of the unstable situation around the Belt) the flexibility of what could be done with the right pods and a tramp freighter made things even more interesting. The Hannex Combisys 'TriLighter' series was this thinking taken to a sort of logical conclusion: An autonomous hover unit that could be stored in a sealed pallet indefinitely until needed. Originally the technology was sold to users who operated remote outposts or other facilities in need of protection, but unable to field more traditional security for whatever reason. Whether licensed or (later) bootlegged these sorts of units became common sights in a variety of small scale conflicts.
The unit we see here was fielded by an unknown party during the separatist violence on Titan. Low gravity worlds with a ready source of liquid reaction mass are an ideal environment for hover units without sophisticated maintenance needs. While too much of an investment to be thought of an truly disposable, such drones may be kept in the field with simple fueling and rearming facilities for a remarkably long time.