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From Pathfinder #180: The Smoking Gun, which isn't enabled.

Blast Suit

ITEM 9
UNCOMMONBULWARKINVESTEDMAGICAL
Price 650 gp
Bulk 2
Category heavy
Group plate
AC Bonus +6
Dex Cap +0
Strength +4
Check Penalty −3
Speed Penalty −10 ft.

Crafted from heavy steel plating and riveted together with cunning precision, this suit of +1 resilient Full Plate is specifically designed to protect against sudden explosions. This added layer of security comes at the cost of movement, however.

Activate command
Trigger You're affected by an area effect that requires a Reflex save, or you would take splash damage from a scatter weapon
Effect The blast suit locks together into a rigid bulwark, protecting you from the blast but preventing you from moving from your position under any circumstances.

You become Immobilized, gain a +2 circumstance bonus to your Reflex save against area effects, and gain resistance 5 to all damage you would normally take from area effects and scatter splash damage (this doesn't damage the blast suit). These effects persist for as long as the suit remains in the locked position. You can Interact with the suit to unlock it.

Effect: Blast Suit

Pathfinder #180: The Smoking GunOGL