First of all, your certificate is stamped. Steel seal is a kind of metal seal with concave and convex feeling, which has an upper part and a lower part. The upper part is connected with the handle, and the lower part sits on the bottom. This is an inseparable whole. When in use, you don't need color media such as inkpad, just put the place where you need to print the steel seal up between the upper and lower parts of the steel seal and press the handle hard. This operation is not easy to cause, and the anti-counterfeiting function is very powerful.