ii TO ALL PARTICIPANTS AND ELIGIBLE DEPENDENTS: On September 6, 1966, the Executive Council of The International Association of Machinists and Aerospace Workers established a nationwide Trust Fund known as the IAM National Health and Welfare Plan. On October 1, 1979, it became a part of the National IAM Benefit Trust Fund (Plan). We are pleased to provide you with this Summary Plan Description (SPD), which describes in detail t he benefits available to active and eligible retired employees and their eligible dependents through the National IAM Benefit Trust Fund effective January 2018 . We urge you to read this SPD carefully so that you may fully understand the benefits available to you and your family. We also suggest that you keep this SPD with your important papers so it will be readily available for future reference. Here are some things to keep in mind: This SPD replaces all other SPDs previously published by the Fund. If any changes are made to the Plan’s benefits provisions, they will be communicated to you via a notice that will be sent to the last known mailing address the Fund Office has on file for you. Therefore, it is extremely important that you notify the Fund Office if you change your mailing address. The benefits described in the SPD are not guaranteed (vested). All benefits may be changed, reduced or eliminated at any time by the Board of Trustees, to the extent allowed by law. The Board reserves the right to set t he effective date of any Plan change. The information set forth in the SPD is effective for the health and welfare benefits provided by the Plan with respect to all claims incurred on or after January 1, 2018 , unless otherwise stated. The administration o f these benefits and accompanying claims is subject to the terms of any agreements executed between the Trustees and third - party providers of benefits and or services under the terms of the Plan . The Board solely is authorized to interpret the terms of th e Plan and has discretion to decide all questions about the Plan, including questions about your eligibility for benefits, the amount and type of benefits payable to you, and the application of any Plan term or provision. Your Employer or Union Represe nt at ive does not have the authority to interpret and/or apply the Plan on behalf of the Board or to act as an agent of the Board. If you have any questions about your benefits, please write or call the Fund Office. Our staff will be pleased to assist you. Sinc erely, THE BOARD OF TRUSTEES