Fits Standard 3-Ring Binders: These photo sleeves' dimensions are 9.2 x 11.3 inches, fitting standard 8.5 x 11 inch 3-ring binders. Each page features 3 pockets per side, holding six 4 x 6 photos front and back. Each set stores up to 180 photos, making these 4x6 photo sleeves ideal for building or expanding family albums, memory books, scrapbooks, and presentation binders. Thick Polypropylene, Acid-Free Material: Crafted from premium thick polypropylene, these photo album pages for 3 ring binder are acid-free and archival-safe to help prevent yellowing, fading, or photo damage. Reinforced edges and punched holes improve durability, making them suitable for long-term storage and frequent page turning.