http://www.usga.org/rules/equipment-rules.html#!rule-14606 false Equipment Rules - Introduction The Rules of Golf ("the Rules") specify the equipment which may be used to play thegame. These specifications can be found in Rule 4 and Appendix II for golf clubs and Rule 5 and Appendix III for golf balls. In general, they are "descriptive" and "restrictive" in nature - defining what golf equipment should look like and limiting how golf equipment can perform. The main objective of Rules 4 and 5 and Appendices II and III is to ensure that technological advances in the design and manufacture of golf equipment are in the best interests of the game of golf. While not wishing to stifle innovation, the purpose of the equipment Rules is to protect the traditions of the game, to prevent an over-reliance on technological advances rather than on practice and skill, and to preserve skill differentials throughout the game. The USGA's Equipment Standards Committee ("the Committee") is responsible for interpreting and applying the Rules relevant to clubs, balls and other equipment, as well as determining and advising their conformance to the Rules. The Committee is also responsible for recommending modifications to these Rules, if and when changes are believed to be necessary. The USGA achieves consistency in the decision-making process by maintaining a database of all previous decisions. Additionally, over time, the Committee has developed a comprehensive set of "guidelines" based on these decisions to help consistently interpret the equipment Rules. The purpose of this publication is to provide guidelines to manufacturers, rules officials and other interested parties in an effort to assist them in interpreting and applying the Rules on golf clubs and balls. The purpose of the "Field Procedures" section is to offer advice on the procedure an official should follow when faced with an equipment ruling immediately before or during a competition. Many of the Rules with respect to clubs and balls can be technical and complex in nature. However, almost without exception, the equipment Rules become understandable after a brief explanation, or with the aid of a simple diagram. Whenever possible, this Guide will attempt to explain the background of a rule and the objective behind it. Also, where practical, the Guide will offer advice as to how best to carry out any certain measurements. Please note that this Guide should be read in conjunction with the 2012-2015 edition of "The Rules of Golf." In the event of any doubt over the conformity of a club or ball, the Rules of Golf take precedence.