Abacus is an old fashioned 'calculator' that uses colored wooden balls to count the amounts. This clock was inspired by this ancient device. - Raw material: 15mm birch plywood board and 12 colored wooden balls - Manufacturing process: the 13 concentric rings that compose the dial are laser cut off the 15mm plywood board. After polishing the rings are fixed together with wooden rods that also hold the colored balls. The balls are painted 12 glossy shades of the rainbow, while the rings remain natural (light brown). - The movement: is silent (non-ticking), second hand sweeps around. It runs with 1pc AA type 1.5V battery (not included in the package). Hands are made of black plastic. Measurements: (W)59cm, (D)3.5cm, (H)59cm (Ø)59cm - Weight: 1.5kg Colour(s): Natural Wood Tone, Multicolor, Material(s): Plywood (birch)