In the counterweight fly system sheaves help guide and direct the wire rope cables which support the batten and the arbor. Most of the sheaves in this system are anchored to the grid. The sheaves guide each cable from the arbor, across the grid, and down to its respective pick point on the batten.

A sheave which changes the direction of a cable is known as a mule block.

Part of the Stage Rigging Metanode