This Cyclo 7/32" hex key is used to change out the VTS-063 VES Head Counterweights behind the heads on a Cyclo dual head polishing tool. VES counterweights are changed out when switching between Cyclo Brush Heads and VTS-2567 ProGuard Orbital backing plates. 

In order to get to the counterweights, you'll need to remove the heads with the Cyclo Flat Wrench VTS-1089. The flat profile allows the wrench to slide into the tight clearance behind the heads. Heads are removed when they become worn or when switching between brushes and other backing plates.