Product description Fasten the plastic clip to the groove, and press it to make it more stable. The direction of the clip is indicated by an arrow and TOP. The four clips should be kept at the same height. Adjust the position of the plastic clips to adjust the height of each shelf. Slip the shelf into the pole and gently press it. The shelf cone is smaller at the top and larger at the bottom. Adjust the level (bottom) to ensure stability. (In case the ground is not flat. )