G PHYSICS
G01 MEASURING; TESTING
G01D MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
21/00 Measuring or testing not otherwise provided for
G01D21/02 Measuring two or more variables by means not covered by a single other subclass