NEC FD1165 - Page 86

The code is interpreted as follows.
a. Head code.
CPOMS
CFOMS
Pan-head metric screw with cross groove
Flat-head metric screw with the cross
groove
AHEXON
BHEXON
SOWA
POWA
#20LWA
A-type hexagon nut
B-type hexagon nut
Small washer
Polished washer
Spring washer
L-CPOMS
S-CPOMS
P-CPOMS
SL-CPOMS
PL-CPOMS
SEMUSU screw (see Item e)
The symbol 0 is replaced by one of the following codes to
show the material type that is used.
= Iron
= Brass
Spring Steel
I
B
ST =
b. Nominal diameter in mm.
c. Length in mm. (Not used for nuts and washers.)
6-2