Dear
Thank you for your letter of (date) in which you
informed us that (product) you purchased was (nature
of problem).
We are sorry that you experienced this problem and are
enclosing (nature of compensation). While we make every
attempt to ensure that our products are (address
complaint), this unfortunate incident can occasionally
occur.
We are very appreciative that you have taken the time to
bring this to our attention and would like to thank you
for purchasing our products.