This is the difference between a GripEdge RPT Hex and a standard Hex tool. Our GripEdge RPT Hex has Rounding Prevention Technology (RPT), which prevents damage from happening to Hex fasteners. They are a complete replacement for your standard Hex sets; use them on brand new fasteners and get up to 50% more Grip, and when used on damaged fasteners, get up to 400% more Grip. #enginerepair #automotiverepair #HandTools #gripedge #mechanic | GripEdge Tools