Although a standard Telescopic Adapter from the Nozzle Tube System can be used on an Active Donut Manifold it may have to be fitted with a locknut to prevent excess thread engagement blocking the internal flow. In addition, the overall length of the standard Telescopic Adapter with a Collet Fitting may be excessive for tool grinding machines with the smallest grinding wheel fitted if the nozzle length also has to suit the largest wheel. This special Telescopic Adapter has a short male thread to face seal onto the Donut, and has a recessed female thread to face seal onto the Collet Fitting. All Telescopic Adapters give 1.5” of linear adjustment, with a Collet Fitting attached, to compensate for 3” of wheel diameter adjustment. The photo shows the adapter on it’s own, plus one connecting a donut to a collet fitting.