dva merilnika pretoka (R2 in R3) zaporedno vgrajena v vode "sonda, filter, črpalka, ventil, vreča" (S2, F2, P2, V2, Sa ter S3, F3, P3, V3, Sb), ki omogočata stalno vizualno preverjanje trenutnega pretoka odvzetega vzorca;
two rotameters (R2 and R3) installed in series in the lines "probe, filter, pump, valve, bag" (S2, F2, P2, V2, Sa and S3, F3, P3, V3, Sb respectively) so that instant visual checks can be made on the flow of the sample at any moment;