US Patent 7789772 Golf club head with improved mass distribution

A golf club head having a striking wall, a front surface, a sole portion extending rearwardly from the rear surface, the sole portion having a forward end, a rearward end, an upper surface and a lower surface. The intersection of the upper surface and the rear surface defines an interior sole line. The intersection of the upper surface and the rearward end defines a trailing edge exterior sole line. The upper surface includes variation in heel-to-toe contour in at least one of: height of the trailing edge or exterior sole line relative to height of the interior sole line; height of the interior sole line relative to height of the outer periphery of the head; height of the trailing edge or exterior sole line relative to height of the outer periphery of the head; and concavity in forward-to-rear contour.