According to one of the questions for the item it is about a foot long. The dimensions given must be off...
I have not used that chemical and have always been hesitant to use these selective herbicides.... I weed by hand, but I have the same problem like you do: some Bermuda grass and sprouts from this ornamental grass colony that I have growing in the front yard seemingly always coming up right from below the spiniest, sharpest, hardest to reach spots. I have been lucky on occasion that by repeated pulling when it grows to where I can reach it to get some of it, but usually it will just come back.
So I am definitely going to use this gripper... Thanks Baja for showing that to us.