Erasers for dry erase boards and chalk boards are sized with students' hands in mind.  One piece dense felt construction will not unravel for extended use.  Erasers measure 2 x 2 x 1.  Set includes 12 erasers and 12 colored markers for use with dry erase boards (3 of each color; red, blue, green, yellow.)   Non-toxic fine point pens erase easily.