Hi I'm wondering what some of the item stats mean.

Spcifically the stats of "Belt of Inertial Barrier"
Armor Bonus: +1 (AC Deflection Modifier)
Damage Resistance: Bludgeoning Resist 5/-
Damage Resistance: Slashing Resist 5/-
Damage Vulnerability: Piercing 25% Damage Vulnerability

The first three I understand, but I'm not sure about the last. Does this belt make me 25% more vulnerable to piercing damage, or only 25% of the standard. And what excatly does this mean? Do I take 125%/25% damage of what I would have taken without the belt?

You take 125% damage iso 100%, so you take 25% more damage of the damage done to you.

you take 5 damage iso 4, 13 iso 10, 125 iso 100.

Thank's!

Good to have a board when you don't have the D&D v.3 maual, and the NwN manual is somewhat scarce on details.