To customers: life is full of surprises. Package Includes: Color Yellow/Pink/Blue/White: 1 x Math Roller Stamp or Color Black: 10 x Replacement Ink Item Name: Math Roller Stamp Material: Plastic Single Replacement Ink Capacity: 3ML Features: Educational, Double Roller, Interesting Teaching Size Details: Size: 7.6cm x 6.4cm x 3.2cm Specifications: It is a math rolling stamp that can be carried easily and reused after adding ink. Just roll the stamp, you can quickly print math problems. This math practice stamp can meet all the addition and subtraction numbers of 1-100 and cultivate children's logical calculation ability. It would be a fun and meaningful gift for your children and friends' children. It is constructed of plastic material. The length of the math roller stamp is 7.6cm, the width is 6.4cm, and height is 3.2cm. It is a great educational toy for both boys and girls. Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Wefor excellence. And hope you have a nice day!