Original Vanathane technology with Special precision anodized aluminum inserts.  57mm x 30mm.  Same compound as the All American Plus with the addition of an aluminum core for a tighter fit and greater feedback. 
 
Fo-Mac wheels are retro-style wheels using a compression molding process.  The materials used are much different than urethane wheels of today.  The formulas used are unique and different from each other and can offer a different skating feel.  Many factors will contribute to the performance of a wheel like this; such as weight, floor material, temperature, etc.