Made of importing new material and advanced skill,write smoothly, the color is the same with ordinary ink pen. The word that wrote down by this pen will disappear thoroughly within hours. Widely used in file ,magic show and other field,new and high quality looks just like normal pen, but a great tool for magic trick. Unique design,make fun to your friend with this pen and good gift for your friends. There's no different in appearance but the writing will be disappear automatically gradually about in 2-3 hours.