Help With Cover Letter?

If you know the HR manager, address the letter to him/her. Be sure to mention the position you're applying for. Mention all the things you've written in your question, like knowing the product line, working at the store before, etc. In your letter, explain why you are interested in the position, and what you feel you would be bringing to it. Be sure to list your contact info. If you search online for "cover letter", you can find really good examples of how to compose one. A cover letter should be fairly short and to the point, but if it's worded well, it can help get you an interview. Good luck!