This Disc disbound refill lined paper size of 8.5'' x 11'' , each pack of 100 sheets/200 pages, total in 2 pack(200 sheets/400 pages), 6mm ruled, 37 lines. Acid-free paper for refill paper, each page 100gsm white paper. Paper thick enough to reduce ink penetration. On a smooth paper, you'll be able to write more smoothly. compatible with Levenger Circa, Arc, Office Depot TUL, Martha Stewart, Talia, Happy Planner, and other half-letter size 11-disc notebook and planners. This A4 filler paper perfectly with notebook, daily planner in school, office and home.