Toshiba TECRA M5 Maintenance Manual page 313

4.1 General
Color of Screw Shaft
To avoid mistakes on the screw length, screw shafts are colored as follows:
Even number length screw:
Odd number length screw:
Special length screw:
Screws whose lengths are indicated to one or more decimal places such as 2.5 mm or 2.8 mm.
Marking of Screws on the Computer Body
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.
Kind of screws
BIND screw
FLAT HEAD screw
SUPER THIN HEAD screw
TAPPING screw
Other screws
(Unique screws, STUD, etc.)
Examples:
6 mm BIND screw
12 mm BIND screw
4 mm FLAT HEAD screw
(Indicates the screwed length in round number regardless the length of the stud.)
TECRA M5 Maintenance Manual (960-542)
brown
white
blue
Symbol
B
F
S
T
U
B6
B12
F4
[CONFIDENTIAL]
4 Replacement Procedures
4-7