Michigan Self Inking Address Stamp Michigan Self Inking Address Stamp Customization Instructions: Approximately ONE hour after you order you will receive an automated email from us, please reply to that email stating your customization Custom Return Address Stamp is self inking. Impression can last for up to one thousand impressions before being reinked. Custom Address Stamp impression is approximately 7/8" x 2-3/8" in diameter. Default color is BLACK unless otherwise stated in Customization. All orders are made to order. Most orders ship within 24 business hours of your customization being received.