love this product Math Trekker™Addition & Subtraction
This math trekker means addition and subtraction practice anywhere. It works just like ordinary flash cards, but the pocket-friendly size and electronic system make it easier to take on-the-go.
- 4'' W x 6'' H x 1.2'' D
- Requires three AG13/LR44 batteries (included)
- Recommended for ages 6 years and up