Send this letter to customers, inviting them to fill out a survey or questionnaire.
{Date}
To: {Name}
{Address}
{City, State, Zip}
Dear {Recipient},
I am wondering if you would be able to help me out regarding {a customer survey, questionnaire, etc.}.
Your assistance in this matter would really help {name of company} better understand our customers' needs and allow us to better serve you in the future.
I would appreciate you getting back to me on this as soon as you can. As a thank you, I have enclosed {coupon, free product, etc.}.
Thank you,
{Sender}