The recently developed filter ozonometer MICROTOPS II No. 3128 (MTops 3128) was purchased in October 1996. Almost two years of intensive comparative measurements with the regular spectrometers Dobson No. 104 (D104) and Brewer No. 10 (BR10) and intercomparison with the standard Dobsons No. 065 (D065) and 064 (D064) on selected days confirmed that the handy MTops 3128 is able to yield good total ozone measurements. The differences between the various instruments are mostly less than ¿ 2%, increasing at air masses higher than 3.5 or at hazy sky conditions. Both instrumental types contribute to this increase with opposite effects. The handling during observation and data processing turned out to be easy with only few minor shortcomings. Replacement of the quartz cover didn't change the original MTops calibration significantly. Adverse effects of the filter aging or a calibration drift could not be detected over this 21-months period. ¿ 1999 American Geophysical Union