Razortail

The unique belt "razortail" lists a mod of "Piercing Attack (33)" on Arreat Summit. Does this mean it conveys a 33% chance of piercing? I'm playing a bowazon, and I'm trying to figure out how much skill-based pierce is needed to achieve 100% piercing attack, if I use razortail. Thanks.|||As Arreat Summit states Razortail adds 33% to your chance of Piercing a target. So to achieve 100% Pierce you would need 67+% more from other items or the skill Pierce itself.
With the skill alone this has to be at least level 9, so you get 69% + 33% = 102%.