Developers are applied to the material after the removal of excess penetrant. The developer gets the penetrant to be visible on the surface of where defects are detected in a process called a bleed-out. The types of developers that Berg offers from Chemetall include non-aqueous, dry powder and water soluble solutions. Please browse our categories to find the best product for you. If you have any questions, please call us at 1-847-577-3980 or send an email to email@example.com. Our knowledgeable staff is there to help.