Address Stamp Custom Custom Ink Personalization Return address stamps, personalize up to 3 lines of text on this customizable auto-inkjet stamp. Address label, return address stamp, small :9/16" x 1-1/2" - Medium :11/16" x 1-7/8" - Large :15/16" x 2-3/8". Color options - Black, blue, green, red and purple. The self-inking design allows for fast, repetitive stamping and clear mounting of the bottom. We use quality machinery and materials to ensure a clear impression and lasting stamp.