We upgraded all of our Solid Steel Ferrule broadheads by adding a Titanium Nitride (Ti-N) coating to the ferrule. The Result: A hardened surface for increased impact durability, reduced friction for unsurpassed penetration and reduced wind drag during flight.We didn't stop there. Another 2009 upgrade: we've scalloped the ferrules to reduce surface area this also reduces wind drag and increases penetration. The 100 grain, 3 blade delivers a 1-1/8 inch cutting diameter, and the 125 grain, 3 blade features a 1-1/4 inch cutting diameter.