I was using System Mechanic 6 and its incinerator option that let you deleted files "up to military grade" it claimed. Upon advise from this forum I uninstalled all my add-on programs like S.M. 6. So I need to get a new file shredder. I heard that if you delete something from your PC it can be reconstructed. I from time to time need something I know will make the file unreachable to anyone. Is there such a product and if so which ones are the best?

Think of deleting a file, as tearing the Table of Contents out of a book.
How to navigate through the book is missing, but the contents of the book is still there.

Shredding makes a selected number of passes, back and forth over the file, with 1's and 0's.
The same as passing a book through a shredder, over and over.
The more passes, the less the chance of reconstructing the book (file).

Spybot has a shredder feature.
Tools / Secure Shredder
Drag the file into the open box.
At the bottom, select the number of shreds.
Click the Chop it away! button.
Use 4 shreds or more, to be sure the file isn't able to be recovered, without the use of some expensive software.

You can also use third-party software, which is what I do.
I use Eraser.
It adds an entry to the context menu (right-click menu), which, for me, is easier to use.
Just right-click the file, and select Erase.
It can also be set, to the number of shredding passes you want to use.

I, too, habitually use Eraser.
Regards,
John

I am "Black helocopter" paranoid, so I too make use of Eraser. It is only over kill if you never have a problem with stolen data.