By default, the effects specified by the bone lattice flexor channels are driven by the child joints of the joints whose bones you selected for them when you created the flexors. This is what you would usually want for most character setup situations. However, you can assign any other joint in the skeleton to drive them. (See Reassign bone lattice flexor joints.)

To edit channels with the Channel Box

1. Select a bone lattice flexor node (default name: boneFlexorn).
2. Set the channels.
3. Click the name of the channel name you want to edit.
4. In your scene, -click and move the mouse to the left or right. By moving the mouse, you interactively change the value of the selected channel. As you move the mouse, note that pressing the key gives you finer control, and pressing the key gives you less control.