进一退二法倍投图片

简介：Wax pills are the best choice for conveying confidential information in this era. When making it, first write the content of the letter with special ink on oily paper that is not afraid of hot oil, stuff it into a small spherical container, and then fill the container with wax juice. After the wax juice cools and solidifies, the outer container is peeled off, and a smooth and opaque wax pill secret message is made.