REFER TO THE IMAGE FOR THE CORRECT SCREW FOR YOUR NIBBLER
The screws for the T and R Nibblers USED TO BE different sizes, but were changed to be the same size in 2020.
To make sure you buy the correct screw for your Nibbler, check the end for a dimple. If there is a dimple on your T Nibbler you need the M2 screw, if there is no dimple on your T Nibbler you need the M1.8 screw. ALL R Nibblers ever sold will use the M2 screw, irrespective of whether there is a dimple or not.
R Nibbler without dimple = M2
R Nibbler with dimple = M2
T Nibbler with dimple = M2
T Nibbler without dimple = M1.8