The frame, rods, and beam
The frame holds everything steady. Vertical rods represent place values, while the horizontal reckoning beam divides the upper and lower beads.
BeamRods
Heaven and earth beads
Each rod has one upper heaven bead, worth 5, and four lower earth beads, worth 1 each. Together they can show every digit from 0 to 9.
The one rule to remember
A bead counts only when it moves toward and touches the reckoning beam.
Beads resting at the outer edges are inactive. Move the heaven bead down to add 5. Move earth beads up to add 1 each. To clear a rod, move every bead away from the beam.