Aervoe's Crown Prussian Blue High Spot Indicator is formulated to provide visual identification of high spots prior to component assembly. Benefits: This product is packaged in the preferred aerosol manner for ease of use by machinists. Formulated to provide a very thin coating on the substrate to be matched, for ease of high spot identification and clean up. Using this product will significantly reduce the amount of time required to ensure that bearings, shafts and housings do not have points of interference which will reduce heat and wear resulting in a longer life of the component.