[Digital Teaching Stamp Roller] Adjustable numbers, gently rolling, can efficiently and quickly print out math practice questions within 100, it is a fun and meaningful gift for your children or friends' children![Mathematics Skill Development] Rotate and adjust the column, and 10 different queuing methods can be adjusted. Satisfy all addition and subtraction numbers from 1-100, and cultivate children's logical calculation ability.[Quick Addition and Subtraction] You can quickly prepare math problems for your kids at home, just roll the stamp, you can quickly print math problems, and it dries quickly, convenient and practical.Arrangement needs to be changed every 10 math problems to avoid duplication[Reusable] Small and exquisite, easy to carry, and can be reused after adding ink. The imprint is clear, the color does not fade after drying, and it is not easy to smudge.[Best Gifts] The roller digital stamp is great for wonderful Christmas birthdays Easter gifts for kids and other occasions. This is a special gift for kids, family, and friends.