Ultra-Durable 180gsm Cardstock: Crafted to withstand frequent handling, these index cards resist bending and ink bleed-through. Ideal for use with markers, pens, and highlighters, they maintain integrity even under rigorous use. Assorted Vibrant Colors: This set includes 50 sheets each of white, pink, purple, blue, and yellow cards, making it easy to organize information by subject or priority and enhancing visual learning and memory retention. Includes Convenient Key Ring: Each pack comes with a durable key ring that keeps your flashcards neatly organized and portable. This feature is perfect for students and professionals who need to study or reference information on the move. Versatile and Practical: These cards are not just for studying! Use them for crafting to-do lists, jotting down vocabulary, planning projects, or setting reminders. Their versatility makes them a must-have for students, educators, and professionals. Smooth Writing Surface: The premium-quality, lightly textured cardstock ensures excellent ink adhesion and smooth writing. Whether you're using a pen, pencil, or highlighter, these cards provide a superior writing experience. Color: Mixed Color Material: Paper Package Contents: 250*colored index cards