The sets of grey beads (like in MA34) are placed in a small wooden box with lid. There are two different shades of grey to distinguish the role in each bar. This article is also available without the box (MA36-A). The beads have a diameter of 8 mm and are micro lathed and varnished in Italy and thread on stainless steel wire by hand.
GREY BEAD STAIRS FOR SUBTRACTION
This material can be used from the age of 4 onwards when the child knows the the golden bar of tens, the numbers 1 to 10 and the coloured bead bars. The goal is to memorize subtractions.