The specifications in Appendix II, 5, with regard to roughness, material and markings in the impact area, do not apply to putters. However, any grooves or other permissable markings on a putter face must not have sharp edges or raised lips.
In addition, if a groove or the grooves on the face of a putter exceed 0.035 inches (0.9mm) in width and 0.020 inches (0.508mm) in depth, the following guidelines apply:
• The width may not exceed 0.060 inches (1.524mm);
• The width to spacing ratio must be no less than 1:1; and
• The depth must be less than the width, and may not exceed 0.040 inches (1.016mm).