self-inking stamp Size of box: 140X60X38mm 8pcs/display box X24/ inner box X6/ctn 2.4' This kind of self-inking stamp is made of the material ABS. At the same time, we produce different types of self-inking stamps in various materials such as PS,PP. The quality of stamp is guaranteed by test report under EN71 part3 and ASTM. What is the advantage of self-inking stamp is that you don't need an ink pad as the ink is in the stamp. It's generally used as tools for handmade cards and scrapbook, which is very popular for children and teenagers.