How do I know my meter size?
Look at the first letter of your meter’s serial number:
B = 20 mm (most residential property meters)
C = 25 mm
D = 32 mm
E = 40 mm
F = 50 mm light duty
G = 50 mm heavy duty
H = 80 mm
J = 100 mm
K = 150 mm
L = 200 mm
M = 250 mm
N = 300 mm