This is the original OEM Long Life Diaphragm. Replaces W81710. Fits G2, G3, G4, Ranger, and Zoom Automatic Pool Cleaners. If the cleaner is not moving or moving slow, check the diaphragm for cracks and splits. If any end of the diaphragm is loose then it needs to be replaced. These things cause the cleaner to loose the pulsating action which causes it to move.