Mechanical trap damage inflicted upon the wearer is reduced by 5. It has no effect on magical trap damage.
The effect from this item stacks with other items that mitigate mechanical trap-damage.
Mechanical Trap: a physical (non-magical) hazard that gets sprung on the party as they advance through the adventure. Puzzles are not traps. “Push” damage as a result of not completing a room challenge in time is not a trap.