10-1.2 Using FIMs The FIM serves to orient and separate certain types of First-Class Mail pieces during the facing-canceling process. Mailers must use the appropriate FIM on the following mailpieces: All letter-size BRM — FIM B and FIM C. All letter-size PRM — FIM C. Letter-size CRM and metered reply mail provided as enclosures in automation-price mailings — FIM A. Letter-size mail with information-based indicia (IBI) printed with nonfluorescent ink directly onto the envelope by an IBI meter or a PC Postage system — FIM D. Cards and letter-size envelopes containing absentee balloting materials — FIM C. A mailer may not use a FIM on other types of mail, except on a letter-size envelope with a permit imprint when that envelope is designed for use as a reusable mailpiece. A FIM used for this purpose must be the appropriate FIM for the postage payment method on the returned envelope.