This pencil refill box is perfect for those who use mechanical pencils with a 0.5mm or 0.7mm lead size. With one box, you'll have plenty of refills to keep your pencil going for a long time. These refills are high-quality and will provide a smooth writing experience. They are easy to install and will fit perfectly into your mechanical pencil. Whether you're a student, artist, or professional, these pencil refills are a must-have for anyone who uses mechanical pencils regularly.