Knobless Cylinders A set of 4 boxes each containing cylinders corresponding to each of the cylinder blocks. The cylinders vary in diameter and height similar to the cylinder blocks. There are 10 blue cylinders corresponding to block "A", 10 red corresponding to block "B", 10 yellow corresponding to block "C", 10 green corresponding to block "D". Each of the blocks teaches a different relationship between the basic dimensions of height and width. Qty :