Features: ARITHMETIC CALCULATION SKILLSYou can quickly prepare math problems for your kids at home. You can print quickly by just scrolling through the math problems, and it dries quickly. This maths toys can help children have fun in learning and improve their arithmetic calculation skills at the same time. CLEAR PRINTThe imprint is clear, and it dries and does not fade after printing, and it is not easy to smudge.Interesting teaching,let children like learning more.Rolling math questions appear instantly, easy to operate and very fast. CUTE AND PRACTICAL100 algorithm questions.Take your math scores to nexts level.Primary school students make a page a day to improve the speed and accuracy of oral arithmetic, cute and practical.You will get 1pc addition and 1pc subtraction roller stamp. ADJUSTABLE NUMBERSAjustable numbers, gently scrolling, Can efficiently and quickly print out less than 100 math questions. Small and exquisite, easy to carry, can add ink for reuse. It can help kids learning and developing intelligence. The best choice for kids gifts! WITH INK OILYou will get 2pcs ink oil ,Oil hole refueling, add ink, can be recycled, ink aligned with the refueling hole, drop ink can be.Easy use.1. Open the oil cap. 2. Drop 5.6 drops into the oil nozzle at the oil hole. 3. Put the oil cap on well. Description: 1.Adjustable numbers, gently scrolling, Can efficiently and quickly print out less than 100 math questions. Small and exquisite, easy to carry, can add ink for reuse. 2.You can print quickly by just scrolling through the math problems, and it dries quickly. Meet all additional or subtraction numbersfor your children. 3.They do not need to be constantly dipped in ink as they are on a roller with the ink stored inside. To refill the ink you just pour it into the black compartments on the side after removing the cap. Specifications: Material: plastic material Color: blue,red Size(about): 6x5.5x5cm/2.36x2.17x1.97in(LxWxT) Gender: unisex. Features: Educational Package Included: 2pcs x Roller Digital Teaching Stamp 2pcs x Oil ink Note: 1. Due to the light and screen difference, the item's color may be slightly different from the pictures. 2. Please allow 0.5-2 cm differences due to manual measurement.