Toshiba Portege M200 Maintenance Manual page 196

4.1 Overview
Screw Notation
To make maintenance of the computer easier, markings of the kinds of the screws
including the types and lengths of the screws are indicated on the computer body.
Format:
Screw shape + Screw length (mm)
Screw shape
B: Bind screw
F: Flat head screw
S: Super thin head screw
T: Tapping screw
U: Other screws (Unique screws: pan head, stud, etc.)
Example: B6 ... 6mm BIND screw
Portege M200 Maintenance Manual (960-457)
4 Replacement Procedures
4-7