Dear Ms. Jones,
In reference to your job posting, I am applying for your Product Manager position with this letter. Please find my enclosed resume for your consideration.
Though my resume details a lot more about my extensive experience and capabilities, I will offer a brief overview here. I have been a successful and happy Product Manager for Cross Country Automotive Services for the past eight years. Though content in my present position, I was moved to apply for this position with your company, as I have always admired your product lines and customer service. I wish to be a part of your well known and long term success. What I will bring is my knowledge of your product lines, knowledge of the industry, and my experience working hard as a Product Manager.
Please get in touch with me, and I will tell you more about my career background. I can be reached at (555)-555-5555 at any time. Thanks for considering me for this very promising position.