Corner card (philately)

• Partial request corner cards are a mere outline, letting the sender fill in the number of days for an undelivered envelope to remain before return plus the sender's entire name and address, e.g. "After __ days, return to...";
• General request corner cards have the printed name of the state or possession, e.g. "Philippine Islands";
• Post Office request corner cards have the printed specific name of the post office, e.g. "Cristobal, Canal Zone";
• Special request corner cards have the full name and address of the sender. These were used by commercial concerns with a large volume of correspondence. They would normally be ordered in multiples of 500.