High Pain Threshold

High Pain Threshold is one of Fallout GURPS advantages. See: Fallout GURPS.

Overview
"You are as susceptible to injury as anyone else, but you don't feel it as much. If you are hurt in combat, you are not stunned and do not have a shock penalty on your next turn. (Exception: a head blow can still stun you.) If you are tortured physically, you are at a +3 to resist. The GM may let you roll at +3 to ignore pain in other situations."

- Steve Jackson Games GURPS sources

In Fallout
With the abandonment of GURPS, High Pain Threshold was recycled, image used for damage resistance.