Features 1. Digital Teaching Stamp Roller: With adjustable numbers, it gently rolls to efficiently print math practice questions up to 100, making it a fun and meaningful gift for your children and friends' children! 2. Enhance Learning Efficiency: Quickly prepare math problems at home; just roll the stamp to print problems that dry fast, making it convenient and practical. Change the arrangement every 10 math problems to prevent duplication. 3. Rapid Addition and Subtraction: Prepare math problems swiftly at home by rolling the stamp, which prints quickly and dries fast. Do remember to change the arrangement every 10 problems to avoid repetition. 4. Reusable Design: Compact and exquisite, easy to carry, and can be reused by adding ink. The imprint is clear, colors won't fade after drying, and it's resistant to smudging. 5. Educational Gift: This is an excellent present for children needing math practice, allowing parents to prepare problems quickly, and enabling kids to assist each other while learning together. Specification Material: Plastic Color: Pink, Blue Size: 10 x 10 x 5 cm Weight: 320 g Package Includes: 4x Math Roller Stamp