udunits/src/main/java/ucar/units/ScaledUnit.java
@Override
    protected Unit myMultiplyBy(final Unit that) throws MultiplyException {
        return that instanceof ScaledUnit
                ? new ScaledUnit(getScale() * ((ScaledUnit) that).getScale(),
                        getUnit().multiplyBy(((ScaledUnit) that).getUnit()))
                : new ScaledUnit(getScale(), getUnit().multiplyBy(that));
    }
@Override
    protected Unit myMultiplyBy(final Unit that) throws MultiplyException {
        return that instanceof ScaledUnit
                ? new ScaledUnit(getScale() * ((ScaledUnit) that).getScale(),
                        getUnit().multiplyBy(((ScaledUnit) that).getUnit()))
                : new ScaledUnit(getScale(), getUnit().multiplyBy(that));
    }
Multiplies this unit by another unit.

@param that
The other unit.
@return The product of this unit and the other unit.
@throws MultiplyException
Can't multiply these units together.