Repair Tool (Subnautica)
The Welder is a tool used to repair damage to vehicles. Currently, it is used to replenish the health of the Seamoth and repair breaches in the hull of the Cyclops and seabase modules. It can also be used to repair the sparks coming from the panel next to the Fabricator in the Lifepod. This doesn't seem to serve a purpose, besides stopping the sparks from emitting, at this particular stage.
It has an energy level which can be replenished with a battery.