The perfect choice for professionals and DIY enthusiasts alike. Thanks to it's unique 120mm retractable, interchangeable leads, the Acer deep hole pencil can mark through beams & joists with ease. Generation 2 - It has new cardboard packaging, higher quality plastic used in manufacture of pen and pencil, improved grip of the lead in the pencil, and sharpener has now moved to the holster instead of having a removable top.