Custom Rubber Stamp Address - Conch Shell Address Stamp - Custom Self Inking Stamp Custom Rubber Stamp Address - Conch Shell Address Stamp - Custom Self Inking Stamp To customize, please click on the 'Customize Now' button on the right. Custom Return Address Stamp is self inking. Impression can last for up to one thousand impressions before being re-inked. Custom Address Stamp impression is approximately 1.65" in diameter. All orders are made to order. Most orders ship within 24 business hours