If you're writing to several people, "Dear Sirs:" is correct. A letter of requirement, or a request letter, is a document that requests specifics such as information, materials, feedback or a pay raise.How to use this sample letter: 1. Read the background below. 2. We request you to issue an Irrevocable Letter of Credit in accordance with the following terms. Don't let bad credit scare you away from an apartment. Write a letter explaining credit problems to your landlord and get a fighting chance. Dear Applicant: Thank you for your application for credit. The following information is needed to make a decision on your application: _____. Dear Mr. Rollins: I am writing to you today to express my interest in a summer internship with the Quantcast Product Group.