Introducing a new form of sustainability for mechanical pencil lead, the Uni Smudge-Proof Lead Refill in cardboard packaging allows repeated use of your current case without discarding it. Currently, disposable plastic cases dominate the market, but users have expressed concerns about waste and the accumulation of empty cases. Inspired by refill systems for household products, this new refill product was developed to address these concerns and meet the growing societal interest in sustainable consumption. The refilling process is simple and convenient. By peeling off each sealing sticker, you can quickly and directly slide the refill lead housed in the cardboard flutes from the refill package into your main case. The sustainable refill package is made of 96.7% recycled cardboard, featuring a slim 4mm thick design that highlights the natural texture of the material. The entire package, including the paper seals, can be fully recycled. Designed for those who consume a large number of refills daily, the refill pack offers a capacity equivalent to 4 full cases, meeting the demand for bulk purchases. Keeping a refill pack at home allows you to focus without worrying about running. Uni refills also feature high-adhesion Smudge-Proof Technology, ensuring bold, clear writing with minimal smudging. This technology makes the powder adhere closely to the paper, keeping your notes clean even with repeated contact between pages or rubbing with your hands. Additionally, the refills resist smudging even when highlighted, preventing buildup on marker tips and ensuring clean, legible notes. Experience a new consumption style with these sustainable refills, combining environmental responsibility with convenience and performance. 4-Pack 0.5mm HB x 2 (320 Pieces Total)Package Size: 100mm (3.9") x 4mm (0.2") x 110mm (4.3")Package Weight: 10 g (0.4 oz)