The Roll of Duct Tape is an item in The Escapists. It can be bought from Inmates, found in their inventory after knocking them unconscious, or in their desks. It is a very useful material that is used in several crafting recipes.
Duct Tape (or a Length of Rope) can also be used to tie down other inmates or guards to keep them out of action for a few hours. It's useful to disrupt a work schedule, keep an enemy from beating you up during something important, or to make a hostage out of guards during a prison take over attempt. You can also put it on cameras for 60 seconds so the cameras will be blinded (console only).