This will help customize your letter for each interviewer as well as remind them of your strengths as a candidate. (thecareerexperts.com)
You can use this for drafting your personal letter to the employer where you are applying if you have a similar situation or else customize the letter according to your needs. (bestsampleresume.com)
That's why it's generally not a good idea to customize your letters by simply changing the name and address at the top. (sciencemag.org)