TRAIT - Construct
A construct is an artificial creature empowered by a force other than necromancy. Constructs are often mindless; they are immune to disease, the Paralyzed condition, and poison; and they may have Hardness based on the materials used to construct their bodies. Constructs are not living creatures, nor are they undead. When reduced to 0 Hit Points, a construct creature is destroyed.
Source: Core Rulebook pg. 630