This half-letter graph paper (5.5 x 8.5 inches) is designed specifically for discbound notebook users who want durable, high-quality refills. Each sheet features mushroom-style hole punches compatible with 8-disc ARC, TUL, and similar discbound systems, allowing pages to be added, removed, or rearranged without damage. Made from 120 GSM premium paper, these sheets are thicker than standard notebook paper, offering a smoother, more substantial writing experience with less ink bleed-through and ghosting. The paper remains printer-friendly while providing excellent performance for everyday writing and technical use. The quad ruled graph layout supports math, engineering, drafting, charts, diagrams, planning spreads, trackers, and design sketches. With 200 sheets per pack, this refill set is ideal for heavy use in school, office, homeschool, or professional environments where organization and flexibility matter. Quad rule squares .25" on each side.