Includes two sizes of magnetic, dry-erasable bonds! Teachers use the large demo bond to model equations on the classroom whiteboard. Students use the smaller bonds to practice on lap boards. Includes 1 large demo bond and 4 student bonds (each bond die cut as a solid piece). Demo bond measures approximately 1 5 1⁄2"W x 12 1⁄3"H. Designed to also be used with Magnetic Two-Color Counters, sold separately.