Lenovo ThinkPad T420 Hardware Maintenance Manual page 127

Step Screw (quantity)
M2 × 3 mm, lat-head, nylon-coated (2)
3
3
4
5
5
Chapter 8
3
4
Color Torque
Black 0.181 Nm
(1.85 kgfcm)
.
Removing and replacing a FRU
121