Zero to ninety nine square grid. Idea for developing numeracy skills. Cover squares or whole strips of numbers and ask children whats hidden underneath. Low cost, roll up, front of class, teaching resource. A dry wipe plastic overlay with holes at top, to fit onto a flip chart easel. Size L. 810mm W. 540mm. Comes with storage tube. If using over a metal whiteboard surface, then our full range of magnetic accessories can also be used (See range : Home page/accessories) If purchasing for use with the Learning with Linden whiteboard easel(code 1a)and overlay holder, then you will also need to purchase 2 battens per overlay. (Choose - Overlay Battens : Home Page/accessories)