Z Chek-D Non Aqueous Developer is a high-performance solvent-based developer used in liquid penetrant inspection, a nondestructive testing method. The developer is applied after the penetrant has been removed and the surface has been dried. Its purpose is to draw the penetrant out of any surface-breaking discontinuities, such as cracks or flaws, making them visible to the naked eye. The product is formulated to create a brilliant white background, which enhances the visibility of these indications.