This letter demands a refund from a company for a product that didn't live up to expectations.
1234, Main Street
Boston, MA 02123
<Recipient Address Goes Here>
<time you purchased the product> I purchased <product purchased> from your company. Since that time I have found that it <description>. That being the case, I must insist on a refund of the full purchase price.
<statement about enclosed receipt and/or product> I would appreciate it if you would send me a refund as soon as possible. I look forward to your prompt attention to this matter. Thank you.
encl: <List of enclosed items goes here>