California Division of Measurement Standards has approved several EZ Meter models for revenue billing within the state. Before they can be installed, they must be tested by the local Weights and Measures inspector. See further details on the main web site about California meters.
The only meters approved by the state are the 100 and 200 amp versions of:
Sequoia - 120 volts to neutral, usually used in marina or RV park for a single boat or vehicle plugged into a 30 amp receptacle.
Denali - like the Sequoia, but serves two separate boats or RVs.
Yosemite - your basic 120/240 volt service found everywhere.
Yellowstone - standard 120/208 volt three phase wye. Due to power company tariffs, rarely used in California for revenue submetering.
California approved meters differ from standard meters in that they count hundredths of kilowatt hours instead of tenths and the faster count for Test mode is disabled. The state requires that the meter can be sealed. The tamper shields satisfy this requirement as does the NEMA4X enclosure. The state also requires that the display counter be clearly labeled with the unit or location name and the resolution of the display. You can use a standard six or seven digit counter with all wheels the same color or you can use a counter with two wheels on the right being a different color to represent hundredths of kwhs. The suggested counter for this use is the sealed 5.2 (Five white wheels and 2 red ones).
The meters have not been submitted to any other government agency for approval