The tab is in the male end of the plug it cable, (the normal cable, not the pigtail) And it shouldn`t be cut off, it`s there to prevent the lighter guage cable to be used with tools that require the thicker cable. (note that this isn't an issue for most European users, because the tools that can be used with a thinner cable come standard with the cable that can also give power to the higher wattage tools)
I have two plugit pigtails, I wanted to put one on my makita planer, and one on my fein supercut, but I really hated it on my supercut so I ended up with one plugit on a concrete vibrator that needed a new cable, and the other one in a box awaiting donation. (it are the ones with the green-not-so-flexible cable)