Used with the Vacu-Box™ and Electrostatic Vacuum Box, this Indented Writing Developing Powder is used in the recovery of Indented Writing. The powder is spread over Type IW film which has been placed over a surface suspected of containing indented writing. No physical contact is ever made with the document, so there is no chance that minute details may be damaged or destroyed. The developing powder adheres to the fine impressions in the document.