Consisting of four 18"(45 cm) long wooden blocks each with ten inset knobbed cylinders graded in height and/or diameter.
In block No.1 - the cylinder increases in both height and diameter.
In block No.2 - Cylinder increases in diameter but remain constant in height.
In block No.3 - Cylinder decreases in height but increases in diameter.
In block No.4 - Cylinder increases in height while diameter remains constant.

Invite the child by telling him you have something to show him. Bring him over to the cylinder blocks and tell him: “These are cylinder blocks.”  Show the child how to carry one of the blocks by gripping the blocks on both sides with both hands and carrying it at waist level and parallel to the ground. Have the child carry the block over to the table and show the child where to place it near the median line of the table. Have the child sit down to your left and then you sit down.

Taking Out
- Begin by pinching from above the knob of the cylinder furthest to the right using you thumb and two fingers. 
- Slowly pull the cylinder out of its hole completely. 
- Place the cylinder standing up in front on the hole.
- Repeat by taking out the cylinder in the same way that is furthest to the left.