The Orenz Sliding Sleeve Mechanical Pencil was developed by Pentel in 2014. Without having to click to advance the lead out, the pencil's mechanism allows the metal sleeve to slide back, exposing just enough lead for you to write, but not enough for you to be able to break the lead. Imagine continuously sketching a line without clicking the pencil at all. (They actually have a fun video to demonstrate below) Pentel was the first company to make 0.5mm lead in the history. In 1960s, as a statement, they took it further to making the finest 0.2mm lead in the world. However, the lead was too thin for most and the pencil wasn’t for everyone except for professionals in drafting. They had to discontinued 0.2mm mechanical pencil. But in 2014, this new mechanism was invented to protect the lead from breaking and 0.2mm mechanical pencil was brought back again.