pf2e.fyi
From Pathfinder Guns & Gears, which isn't enabled.

Blast Resistance

FEAT 5

Access You are from Dongun Hold or Alkenstar.

You're used to the clamor of steel, the crack of a firearm, and the thunderous blast of explosions. You gain resistance 3 to fire and sonic. If you roll a success on a saving throw against an effect that causes the Dazzled or Deafened conditions, you get a critical success instead.

Pathfinder Guns & GearsORC