Sprocket, Vampire Special, 79t

Vampire is a sprocket designed to reduce friction between chain and sprocket. 
During the "release" the roller-chain does not find the resistance, which it normally finds in traditional sprocket, due to the profile of the tooth and the lowering of the newt one.  
The sprocket is made in ERGAL 7075 b, the maximum lightness and quality of the materials, it also has a innovative hard anodizing process OX-W ISO 10074, MIL-A 8625 Type 3, which improves the resistance to corrosion, lower the final roughness, and increases its hardness and smoothness, through a nanometric layer of titanium oxide, on the surface with anti-seize properties.