NShred 

With NShred you can eliminate confidential data from PC drives. Name, size, contents of erased file or folder can never be recovered, by any software or hardware means. Follows standard recommendations, such as US Department of Defense (DOD).
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File Deleter 

File Deleter is an easy-to-use tool for delete files permanently. It can erase all data of deleted files physically without any chance to recover and protect your privacy effectively.
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