This is a 13-rod abacus. The frame measures 6 1/8 x 3 1/4 inches and the bead diameter is 3/8 inch. Red felt backing prevents beads from slipping.
An optional metal coupler is available for linking two abacuses together.
Watch a student-made video explaining some of the functions of the Cranmer Abacus.
- Age Range:
- 5 and Up