The Roller Number Teaching Practice is a fun and educational addition and subtraction learning tool for kids. With its digital teaching chapter and interesting drawings, children can practice addition and subtraction within numbers 1-100. The rotary adjustment design allows for different queue modes, helping develop children's logical calculation ability. It is efficient and fast in generating math problems, making it easy for parents to prepare exercises for their children. The stamp is reusable, making it convenient to use. It is small and exquisite, easy to carry. Perfect as a gift for children and parents alike, providing a moment of silence for parents while keeping the children engaged. Features 1. Digital Teaching Chapter: Addition and Subtraction, interesting drawing, number 1-100. Give your children or your friend kids a funny and meaningful gift! 2. Rotary Adjustment Design: Ten different queue modes can be adjusted. Satisfy all addition and subtraction within numbers 1-100. Develop children's logical calculation ability. 3. Efficient And Fast Math Problems: You can quickly prepare math problems for your child at home. You can quickly complete the quiz by simply scrolling the math problems. 4. Reusable: Small and exquisite, easy to carry, add ink for repeated use. 5. Best Gift: Keeping the children busy and get a moment of silence for yourself when you need. So, this is great gift for our children, even for parents. Specification Material: Plastic Color: Pink, Blue Size: 4 x 3 x 5 cm Weight: 40 g Pattern: Subtraction stamp, Addition stamp Package Include: 1 Digital Teaching Stamp(No Ink)