The line by line debugger of program logic for COBOL programs.

It allows you to do as much testing as you're required to do, to pretty much guarantee that when a program goes into production it's as error-free as possible. None of them are completely ever free, but as error free as possible.

The product is good. I don't really want to minimize this into listing out what features of this product; the product on the whole is totally a great product.