A cloak that imparted complete invisibility with a turn of a switch.

But it was more than just the cloak. It was what the cloak hid underneath.

To give legs to his aging body, NoMan was actually an android with the brain signature of Professor Dunn. But not just one android. Many expensive androids were made, and the mind of Professor Dunn could transfer into any one of those android bodies in a moment's notice - but only one android at a time.

NoMan was human.
NoMan was machine.
Torn between the two, perhaps forever.

Androids are machines first, and capable of failure.

If NoMan, the combination of man and machine, were to fail without Professor Dunn transferring his mind out, his mind would be lost forever.