|
|
| |
CDN. / U.S. |
DIAMETER ( in millimetres ) |
U.K. |
|
CIRCUMFERENCE
( in millimetres ) |
|
4
|
14.8mm
|
H 1/2
|
|
46.5mm
|
|
4 1/2
|
15.2mm
|
I 1/2
|
|
48mm
|
| |
5
|
15.6mm
|
J 1/2
|
|
49mm
|
|
5 1/2
|
16mm
|
L
|
|
50.5mm
|
|
6
|
16.4mm
|
M
|
|
52mm
|
| |
6 1/2
|
16.8mm
|
N
|
|
53mm
|
|
7
|
17.3mm
|
O
|
|
54.5mm
|
|
7 1/2
|
17.7mm
|
P
|
|
55.5mm
|
| |
8
|
18.1mm
|
Q
|
|
57mm
|
|
8 1/2
|
18.5mm
|
Q 1/2
|
|
58mm
|
|
9
|
18.9mm
|
R 1/2
|
|
59.5mm
|
| |
9 1/2
|
19.3mm
|
S 1/2
|
|
61mm
|
|
10
|
19.7mm
|
T 1/2
|
|
62mm
|
|
10 1/2
|
20.1mm
|
U 1/2
|
|
63.5mm
|
| |
11
|
20.6mm
|
V 1/2
|
|
64.5mm
|
|
11 1/2
|
21mm
|
W 1/2
|
|
66mm
|
|
12
|
21.4mm
|
Y
|
|
67.5mm
|
| |
12 1/2
|
21.8mm
|
Z
|
|
68.5mm
|
|
13
|
22.2mm
|
Z+1
|
|
70mm
|
|
13 1/2
|
22.6mm
|
Z+2
|
|
71mm
|
| |
14
|
23mm
|
Z+3
|
|
72.5mm
|
|
14 1/2
|
23.4mm
|
Z+4
|
|
74mm
|
|
15
|
23.9mm
|
Z+5
|
|
75mm
|