The Montessori clock is a wonderful piece that incorporates everything the child has learned to the point before they are learning to tell time.  The skip counting five chains gave way to them learning how to count by fives and it is put to use with this clock in the representation of the five bars in between each numeral representing the minutes between each one.  The clock is made to assemble by the child before use and to disassemble after each use.  A screwdriver, single bolt and washer and the minute hand, second hand, and hour hand are provided for assembly.